fix(stores): add caching to CliSettings.load() to reduce disk I/O

[github-actions]

Summary

Adds LRU caching to CliSettings.load() to prevent repeated disk reads when loading CLI settings.

Changes

• Added @lru_cache to internal _load_cli_settings() function
• Cache is keyed by config file path for test isolation
• Cache is automatically invalidated when save() is called
• Added invalidate_cache() class method for explicit cache clearing

Related Issue

Addresses findings from #761 (Code Quality Report - Low-Hanging Fruit)

Testing

• Linting passes (make lint)
• Tests pass (make test - 1353 tests)

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This PR was automatically generated by the Code Quality Report workflow.

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🚀 Try this PR

uvx --python 3.12 git+https://github.com/OpenHands/OpenHands-CLI.git@fix/code-quality/cli-settings-caching

[enyst]

@OpenHands make an empty commit to kick in CI, then /codereview this PR and /iterate to green and approved from AI reviewer bot

[openhands-ai]

I'm on it! enyst can track my progress at all-hands.dev

[enyst]

🟢 Good taste - Simple, targeted cache extraction with explicit invalidation and path-keyed isolation.

The implementation keeps the persistence behavior intact while removing repeated disk reads from hot call sites. save() clears the cache, callers that need to observe out-of-band file edits now have CliSettings.invalidate_cache(), and the added unit coverage exercises cache hits, explicit invalidation, save invalidation, and path-key isolation.

[RISK ASSESSMENT]

• [Overall PR] ⚠️ Risk Assessment: 🟢 LOW
  Small, localized settings-store change with no public API removal. The main behavioral change is intentional caching; the invalidation path and tests cover the practical stale-read cases.

VERDICT:
✅ Worth merging: Core logic is sound and now has focused regression coverage.

KEY INSIGHT:
The right abstraction here is keeping disk I/O behind a single cached loader while making invalidation explicit at every write boundary.

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This review was created by an AI agent (OpenHands) on behalf of the requester.

[github-actions]

Coverage Report •

File	Stmts	Miss	Cover	Missing
openhands_cli/stores
cli_settings.py	76	0	100%
TOTAL	7072	1011	85%

[openhands-ai]

Since the last summary, there were no additional repository or PR changes.

Checklist:

• ✅ The requested PR work was completed: CI was retriggered, the PR was reviewed, and the PR was iterated to green/approved.
• ✅ No further instructions were pending.
• ✅ No extraneous changes were made after the last summary, so there is nothing to revert.
• ✅ The final state remains: PR fix(stores): add caching to CliSettings.load() to reduce disk I/O #762 is green, approved, mergeable, and has no unresolved review threads.