[AI Improvement] [Task] Remove unused production dependencies proxy-agent, universal-analytics, and @apphosting/common

[joehan]

Resolves Buganizer b/568084099

Proposed Improvement

Removed unused production dependencies proxy-agent, universal-analytics, and @apphosting/common, along with @types/universal-analytics from devDependencies and the universal-analytics uuid override block from package.json. Regenerated npm-shrinkwrap.json using pinned npm@11.9, cleanly removing ~40 unused transitive packages from the published package dependency tree.

Verification

• npm ci: Installed clean lockfile successfully.
• npm run build: TypeScript compilation and build steps succeeded.
• npm run lint:quiet: Passed cleanly across the entire repository (ESLint and Prettier).
• npm run test:compile: Passed cleanly.
• npx mocha src/apiv2.spec.ts src/track.spec.ts: All 54 tests passed.
• Idempotence verification: npx -y npm@11.9 install --package-lock-only --ignore-scripts produces no diff against npm-shrinkwrap.json.

[gemini-code-assist]

Code Review

This pull request removes unused dependencies from package.json, including @apphosting/common, proxy-agent, and universal-analytics (along with its types and overrides), and updates CHANGELOG.md accordingly. As there are no review comments, I have no additional feedback to provide.