fix(rm): preserve recursive purge semantics

[overtrue]

Summary

• Route recursive rm --purge through single-object delete requests so RustFS applies force-delete semantics to each object.
• Align the CORS stdin integration assertion with the existing camelCase JSON output contract.

Evidence

• The scheduled Full Integration run on main failed in bucket_operations::test_bucket_cors_set_accepts_stdin_source and version_operations::test_rm_recursive_purge_permanently_deletes_versioned_prefix.
• Both failures reproduced locally against rustfs/rustfs:latest using an isolated RustFS container.
• Recursive purge reported deleted keys, but version list still showed delete markers and original versions because the batch delete path did not purge versions on latest RustFS.

Safety

• Non-purge recursive deletion still uses the existing batch delete path.
• The purge path reuses the existing single-object delete behavior already validated by the single-object purge integration test.
• The CORS change only updates the test assertion to match the existing public JSON shape.

Validation

• cargo test --package rustfs-cli --test integration --features integration bucket_operations::test_bucket_cors_set_accepts_stdin_source -- --exact --test-threads=1
• cargo test --package rustfs-cli --test integration --features integration version_operations::test_rm_recursive_purge_permanently_deletes_versioned_prefix -- --exact --test-threads=1
• cargo test --package rustfs-cli --test integration --features integration -- --test-threads=1
• make pre-commit

[Copilot]

Pull request overview

This PR fixes recursive rm --purge behavior by ensuring each object under a prefix is force-deleted via single-object delete requests (matching RustFS semantics), and updates a CORS stdin integration test assertion to match the existing camelCase JSON output contract.

Changes:

• Route recursive purge deletes through delete_single (one request per key) instead of the batch delete path.
• Update CORS integration test to assert allowedMethods rather than allowed_methods in JSON output.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
crates/cli/tests/integration.rs	Adjusts CORS JSON assertion to use the camelCase allowedMethods field.
crates/cli/src/commands/rm.rs	Adds a dedicated recursive --purge path that deletes keys individually via the single-object delete API.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.