Migrate microsoft.azure provider to azure-batch 15.x

[Subham-KRLX]

Migrates the microsoft.azure provider to azure-batch 15.x (Track 2 SDK), unblocking the dependency cap from #66452.

Key Changes

• Dependency: Removed the <15.0.0 cap in pyproject.toml and updated uv.lock.
• AzureBatchHook: Swapped BatchServiceClient with BatchClient, SharedKeyCredentials with AzureNamedKeyCredential, and updated CRUD / model parameter classes.
• AzureBatchOperator: Removed retired os_family/os_version parameters. Updated deferrable mode, term/delete logic, and cleanup methods.
• Tests: Rewrote and updated unit tests (35/35 passing) and static checks.

closes: #66466

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Was generative AI tooling used to co-author this PR?

• Yes — Claude(For code research)

[github-actions]

uv.lock on main just moved via #68620 ("Sync uv.lock and provider-deps checksum for #66612"), commit a42fdb9 and this PR currently conflicts.

Quickest fix:

git fetch upstream main && git rebase upstream/main
rm uv.lock && uv lock
git add uv.lock && git rebase --continue
git push --force-with-lease

Automated nudge — ignore if you're not ready to rebase. This comment is updated in place on future uv.lock bumps.

[LuuOW]

Technical audit: code patterns and implementation verified for alignment with modern software engineering standards.