fix(ci): optimize workflows, fix build ordering, and add caching

[hiSandog]

Summary

This PR addresses several issues in the CI workflows that cause unnecessary build times and includes a correctness fix for a critical build ordering bug.

Changes

1. Critical: Fix npm ci / npm run build ordering in ci.yml

On Linux and Mac CI jobs, npm run build was running before npm ci. This means builds were using potentially stale cached artifacts from previous workflow runs instead of freshly installed dependencies. Fixed by moving npm ci to run before npm run build.

2. Add TypeScript build caching to all major workflows

Added actions/cache@v4 for TypeScript build outputs (packages/*/dist, packages/*/*.tsbuildinfo) to:

• ci.yml (Linux + Mac)
• chained_e2e.yml (Linux + Mac + Evals)
• deflake.yml (Linux + Mac)

This avoids redundant tsc --build recompilation across workflow runs that use the same commit SHA.

3. Add npm dependency caching to E2E workflows

Added cache: 'npm' to setup-node in chained_e2e.yml and deflake.yml, which were missing npm cache configuration entirely.

4. Remove npm cache clean --force on macOS E2E jobs

Both chained_e2e.yml and deflake.yml had a step that forcibly destroyed the npm cache on macOS runners. Removing this allows subsequent workflow runs to benefit from npm dependency caching.

5. Increase vitest thread limits for large packages

Increased maxThreads from 4 to 8 for:

• packages/core/vitest.config.ts (909 test files)
• packages/cli/vitest.config.ts (233 test files)

The 4-thread limit was unnecessarily constraining test parallelism on 16-core CI runners.

6. Add LRU eviction to CacheService

Added maxCapacity option to CacheOptions interface in packages/core/src/utils/cache.ts. When the cache exceeds the configured capacity, the least recently used entry is evicted. This prevents unbounded memory growth in long-running or high-throughput scenarios.

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[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request focuses on optimizing the continuous integration pipeline and enhancing the internal caching utility. By correcting build sequences, introducing comprehensive caching strategies, and tuning test parallelism, the changes aim to significantly reduce build times and resource consumption. Additionally, the introduction of an LRU eviction policy for the CacheService ensures better memory management in high-throughput environments.

Highlights

• CI Workflow Optimization: Corrected build ordering in CI jobs, added TypeScript and npm dependency caching, and removed unnecessary cache clearing steps to improve build performance.
• Test Parallelism: Increased Vitest thread limits from 4 to 8 for core and CLI packages to better utilize available CI runner resources.
• CacheService Improvements: Implemented an LRU (Least Recently Used) eviction strategy in CacheService to prevent unbounded memory growth.

Ignored Files

• Ignored by pattern: .github/workflows/** (3)
  • .github/workflows/chained_e2e.yml
  • .github/workflows/ci.yml
  • .github/workflows/deflake.yml

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[gemini-code-assist]

Code Review

This pull request implements a Least Recently Used (LRU) eviction strategy for the CacheService in packages/core by introducing a maxCapacity option and tracking access order for Map-based storage. Additionally, the Vitest configuration for packages/cli and packages/core has been updated to increase maxThreads from 4 to 8. I have no feedback to provide.