Blockwise mask fn as opt arg in all masking functions

[zucchini-nlp]

What does this PR do?

As per title, I think this pattern is used quite often and deserves to be a public mask-fn. Used currently in gemma/paligemma family, GIT, PI0 and will be used in two upcoming models (deepseekOcr and Molmo2)

This PR allows all these models ton go non-vmap path, which iirc is more preferable for us.

I opted for adding 'blockwise_mask' as an arg in existing mask fn, it doesn't seems like a new mask type of itself. We might have to create otherwise - create_blockwise_causal_mask, create_blockwise_sliding_causal_mask, etc.

[HuggingFaceDocBuilderDev]

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[github-actions]

[For maintainers] Suggested jobs to run (before merge)

run-slow: gemma3, gemma4, git, paligemma, pi0

[zucchini-nlp]

run-slow: gemma3, gemma4, git, paligemma, pi0

[github-actions]

Workflow Run ⚙️

This comment contains run-slow, running the specified jobs:

models: ["models/gemma3", "models/gemma4", "models/git", "models/paligemma", "models/pi0"]
quantizations: []

[github-actions]

CI Results

Workflow Run ⚙️

Commit Info

Context	Commit	Description
RUN	36c679a5	workflow commit (merge commit)
PR	e8f06b29	branch commit (from PR)
main	77de8dd8	base commit (on main)

Model CI Report

❌ 17 new failed tests from this PR 😭

• gemma3:
  tests/models/gemma3/test_modeling_gemma3.py::Gemma3IntegrationTest::test_model_4b_batch (❌ ⟹ ❌)
  tests/models/gemma3/test_modeling_gemma3.py::Gemma3IntegrationTest::test_model_4b_batch_crops (❌ ⟹ ❌)
  tests/models/gemma3/test_modeling_gemma3.py::Gemma3IntegrationTest::test_model_4b_bf16 (❌ ⟹ ❌)
  tests/models/gemma3/test_modeling_gemma3.py::Gemma3IntegrationTest::test_model_4b_crops (❌ ⟹ ❌)
  tests/models/gemma3/test_modeling_gemma3.py::Gemma3IntegrationTest::test_model_4b_multiimage (❌ ⟹ ❌)

• gemma4:
  tests/models/gemma4/test_modeling_gemma4.py::Gemma4IntegrationTest::test_export_text_only (❌ ⟹ ❌)

• paligemma:
  tests/models/paligemma/test_modeling_paligemma.py::PaliGemmaForConditionalGenerationIntegrationTest::test_integration_detection_bug (❌ ⟹ ❌)
  tests/models/paligemma/test_modeling_paligemma.py::PaliGemmaForConditionalGenerationIntegrationTest::test_small_model_integration_test (❌ ⟹ ❌)
  tests/models/paligemma/test_modeling_paligemma.py::PaliGemmaForConditionalGenerationIntegrationTest::test_small_model_integration_test_multiimage (❌ ⟹ ❌)
  tests/models/paligemma/test_modeling_paligemma.py::PaliGemmaForConditionalGenerationIntegrationTest::test_small_model_integration_test_paligemma_VQA (❌ ⟹ ❌)
  tests/models/paligemma/test_modeling_paligemma.py::PaliGemmaForConditionalGenerationIntegrationTest::test_small_model_integration_test_paligemma_batched (❌ ⟹ ❌)
  tests/models/paligemma/test_modeling_paligemma.py::PaliGemmaForConditionalGenerationIntegrationTest::test_small_model_integration_test_paligemma_batched_bf16 (❌ ⟹ ❌)
  tests/models/paligemma/test_modeling_paligemma.py::PaliGemmaForConditionalGenerationIntegrationTest::test_small_model_integration_test_paligemma_batched_f16 (❌ ⟹ ❌)
  tests/models/paligemma/test_modeling_paligemma.py::PaliGemmaForConditionalGenerationIntegrationTest::test_small_model_integration_test_paligemma_empty_prompt (❌ ⟹ ❌)

• pi0:
  tests/models/pi0/test_modeling_pi0.py::PI0ModelIntegrationTest::test_pi0_base_libero (❌ ⟹ ❌)
  tests/models/pi0/test_modeling_pi0.py::PI0ModelIntegrationTest::test_pi0_base_reference_values (❌ ⟹ ❌)
  tests/models/pi0/test_modeling_pi0.py::PI0ModelIntegrationTest::test_train_pi0_base_libero (❌ ⟹ ❌)

[zucchini-nlp]

oh, no, I forgot about conversion. Will wait until merged and trigger test again