[Jenia3377543]

Adds the S3 remote write options from treeverse/dvc-s3#173 to the config
schema, so dvc remote modify accepts them instead of failing with
"extra keys not allowed".

• storage_class, object_tags, extra_s3_args: strings, interpreted by dvc-s3
• requester_pays: boolean, default false

Fixes #11122

Related:

• s3: add storage_class, requester_pays, object_tags and extra_s3_args options dvc-s3#173 (implementation)
• docs: document storage_class, requester_pays, object_tags, and extra_s3_args S3 config options dvc.org#5582 (docs)

Testing

• New unit tests in tests/unit/test_config.py (load and validate all four
  options; requester_pays default)
• pytest tests/unit/test_config.py passes; pre-commit hooks (ruff, mypy,
  codespell) pass
• Checked by hand: dvc remote modify myremote requester_pays maybe is rejected

🤖 Generated with Claude Code

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.98%. Comparing base (2431ec6) to head (6796e32).
⚠️ Report is 221 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #11123      +/-   ##
==========================================
+ Coverage   90.68%   90.98%   +0.30%     
==========================================
  Files         504      505       +1     
  Lines       39795    41153    +1358     
  Branches     3141     3263     +122     
==========================================
+ Hits        36087    37442    +1355     
- Misses       3042     3072      +30     
+ Partials      666      639      -27     

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[Jenia3377543]

Note for reviewers: the lint failures here are not caused by this PR. mypy reports an error in dvc/commands/completion.py:20 (shtab.complete preamble type), a file this PR doesn't touch. The nightly Tests runs on main fail with the same error on the same base commit (56e5982). The tests and the other hooks (ruff, codespell) pass.