[NeMo-UX] Support `load_strictness`
> PL does this like [this](https://github.com/Lightning-AI/pytorch-lightning/pull/19404/files#diff-72f5c7707bc8f4033f0e5f644a8b2eda5d333084e91dfeaaa1368dcbdf24df02). So I feel like we should adopt the same design and not add a custom arg to our strategy.

If only we can propagate this flag to dist_checkpointing.load then using this flag would be ideal > > PL does this like [this](https://github.com/Lightning-AI/pytorch-lightning/pull/19404/files#diff-72f5c7707bc8f4033f0e5f644a8b2eda5d333084e91dfeaaa1368dcbdf24df02). So I feel like we should adopt the same design and not add a custom arg to our strategy.
> 
> If only we can propagate this flag to dist_checkpointing.load then using this flag would be ideal

Yeah, an example of how PL does that can be found [here](https://github.com/Lightning-AI/pytorch-lightning/blob/b35f303561e0de06d559c9ec5322ffaa1a9017c0/src/lightning/pytorch/strategies/fsdp.py#L609). This PR is stale because it has been open for 14 days with no activity. Remove stale label or comment or update or this will be closed in 7 days. This PR was closed because it has been inactive for 7 days since being marked as stale. > > If only we can propagate this flag to dist_checkpointing.load then using this flag would be ideal
> 
> Yeah, an example of how PL does that can be found [here](https://github.com/Lightning-AI/pytorch-lightning/blob/b35f303561e0de06d559c9ec5322ffaa1a9017c0/src/lightning/pytorch/strategies/fsdp.py#L609).

Revisiting this PR. I don't think this is quite what we want. It looks like PTL's `strict` is just passed to `load_model_state_dict`, which is called after the checkpoint is loaded using `dist_checkpointing.load`, so we're not able to propagate the value of `strict` to `dist_checkpointing.load` <!-- pylint-output-strict-mode-false -->

beep boop 🤖: 🙏 The following files have warnings. In case you are familiar with these, please try helping us to improve the code base.

---

Your code was analyzed with PyLint. The following annotations have been identified:

```
************* Module nemo.lightning._strategy_lib
nemo/lightning/_strategy_lib.py:573:0: C0301: Line too long (130/119) (line-too-long)
nemo/lightning/_strategy_lib.py:35:0: C0115: Missing class docstring (missing-class-docstring)
nemo/lightning/_strategy_lib.py:36:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/_strategy_lib.py:139:0: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/_strategy_lib.py:166:0: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/_strategy_lib.py:202:0: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/_strategy_lib.py:515:0: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/_strategy_lib.py:598:0: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/_strategy_lib.py:611:4: C0115: Missing class docstring (missing-class-docstring)
************* Module nemo.lightning.io.pl
nemo/lightning/io/pl.py:82:0: C0301: Line too long (130/119) (line-too-long)
nemo/lightning/io/pl.py:58:0: C0115: Missing class docstring (missing-class-docstring)
nemo/lightning/io/pl.py:64:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/io/pl.py:73:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/io/pl.py:303:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/io/pl.py:308:4: C0116: Missing function or method docstring (missing-function-docstring)
************* Module nemo.lightning.pytorch.callbacks.peft
nemo/lightning/pytorch/callbacks/peft.py:381:0: C0301: Line too long (130/119) (line-too-long)
nemo/lightning/pytorch/callbacks/peft.py:207:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/callbacks/peft.py:324:0: C0115: Missing class docstring (missing-class-docstring)
************* Module nemo.lightning.pytorch.strategies.megatron_strategy
nemo/lightning/pytorch/strategies/megatron_strategy.py:315:0: C0301: Line too long (159/119) (line-too-long)
nemo/lightning/pytorch/strategies/megatron_strategy.py:90:0: C0115: Missing class docstring (missing-class-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:272:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:305:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:386:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:396:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:402:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:445:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:449:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:481:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:491:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:558:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:577:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:604:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:612:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:620:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:624:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:663:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:684:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:719:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:742:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:751:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:759:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:771:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:801:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:826:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:842:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:60:0: W0611: Unused _ModuleStepFunction imported from nemo.lightning.megatron_parallel (unused-import)
nemo/lightning/pytorch/strategies/megatron_strategy.py:76:0: W0611: Unused AdapterPath imported from nemo.lightning.resume (unused-import)

-----------------------------------
Your code has been rated at 9.52/10
```

---

Thank you for improving NeMo's documentation! <!-- pylint-output-strict-mode-false -->

beep boop 🤖: 🙏 The following files have warnings. In case you are familiar with these, please try helping us to improve the code base.

---

Your code was analyzed with PyLint. The following annotations have been identified:

```
************* Module nemo.lightning._strategy_lib
nemo/lightning/_strategy_lib.py:573:0: C0301: Line too long (130/119) (line-too-long)
nemo/lightning/_strategy_lib.py:35:0: C0115: Missing class docstring (missing-class-docstring)
nemo/lightning/_strategy_lib.py:36:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/_strategy_lib.py:139:0: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/_strategy_lib.py:166:0: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/_strategy_lib.py:202:0: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/_strategy_lib.py:515:0: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/_strategy_lib.py:598:0: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/_strategy_lib.py:611:4: C0115: Missing class docstring (missing-class-docstring)
************* Module nemo.lightning.io.pl
nemo/lightning/io/pl.py:82:0: C0301: Line too long (130/119) (line-too-long)
nemo/lightning/io/pl.py:58:0: C0115: Missing class docstring (missing-class-docstring)
nemo/lightning/io/pl.py:64:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/io/pl.py:73:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/io/pl.py:303:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/io/pl.py:308:4: C0116: Missing function or method docstring (missing-function-docstring)
************* Module nemo.lightning.pytorch.callbacks.peft
nemo/lightning/pytorch/callbacks/peft.py:381:0: C0301: Line too long (130/119) (line-too-long)
nemo/lightning/pytorch/callbacks/peft.py:207:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/callbacks/peft.py:324:0: C0115: Missing class docstring (missing-class-docstring)
************* Module nemo.lightning.pytorch.strategies.megatron_strategy
nemo/lightning/pytorch/strategies/megatron_strategy.py:315:0: C0301: Line too long (159/119) (line-too-long)
nemo/lightning/pytorch/strategies/megatron_strategy.py:90:0: C0115: Missing class docstring (missing-class-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:272:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:305:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:386:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:396:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:402:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:445:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:449:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:481:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:491:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:558:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:577:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:604:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:612:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:620:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:624:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:663:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:684:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:719:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:742:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:751:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:759:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:771:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:801:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:826:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:842:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/lightning/pytorch/strategies/megatron_strategy.py:60:0: W0611: Unused _ModuleStepFunction imported from nemo.lightning.megatron_parallel (unused-import)
nemo/lightning/pytorch/strategies/megatron_strategy.py:76:0: W0611: Unused AdapterPath imported from nemo.lightning.resume (unused-import)

-----------------------------------
Your code has been rated at 9.52/10
```

---

Thank you for improving NeMo's documentation! [🤖]: Hi @ashors1 👋,

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