DOC: fix v3 migration guide store table

[nuglifeleoji]

Closes #2699. Closes #2857.

• Removes a truncated/broken table row (| zarr.)
• Adds a migration note for LRUStoreCache, which was removed in v3 with no direct equivalent

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.71%. Comparing base (6599477) to head (8f09ae7).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3850   +/-   ##
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  Coverage   94.71%   94.71%           
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  Files          94       94           
  Lines       13663    13663           
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  Hits        12941    12941           
  Misses        722      722           

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[d-v-b]

maybe this can be updated to refer to the CacheStore that we added to the experimental module.

[d-v-b]

🤖 AI text below 🤖

The agent pushed two commits to this branch, on behalf of @d-v-b, to make it mergeable for 3.4.2:

• e845f6b08 merges main. The only conflict was the truncated | zarr. row, which docs: fix errors and improve consistency across the documentation #4132 had already removed, so main's version was kept.
• 7783ebf92 reworks the LRUStoreCache note:
  • Moves LRUStoreCache from the "deprecated stores" list into the renamed-stores table, since it was not deprecated in 2.x (see DOC: LRUStoreCache removed in Zarr 3.0, not documented #2857). It now maps to the experimental zarr.experimental.cache_store.CacheStore, as suggested in the inline review comment.
  • Adds a short paragraph that links to the CacheStore section of the experimental guide.
  • Fixes the fsspec reference: fsspec.implementations.caching does not exist, and the caching filesystems live in fsspec.implementations.cached.
  • Adds changes/3850.doc.md.

mkdocs build --strict passes locally.

Other 2.x stores are still missing from the migration guide: NestedDirectoryStore, KVStore/DictStore, ConsolidatedMetadataStore and N5FSStore. They are left for a follow-up.