chore: reduce bundle size by 50%

[lvndry]

Summary

This PR achieves a ~50% reduction in bundle size by replacing the monolithic googleapis dependency with scoped Google API packages and optimizing the build pipeline to externalize heavy UI/runtime dependencies from the bundled output.

Key Changes

🔄 Google API Dependency Split

• Replaced googleapis (monolithic package) with scoped packages:
  • @googleapis/gmail (v16.1.1)
  • @googleapis/calendar (v14.2.0)
  • googleapis-common (v8.0.1)
• Refactored Gmail and Calendar services to use scoped imports:
  • Changed from google.auth.OAuth2 → auth.OAuth2 (from scoped packages)
  • Changed from google.gmail() → gmail() (from @googleapis/gmail)
  • Changed from google.calendar() → calendar() (from @googleapis/calendar)
• Updated all service tests to match new import patterns

🏗️ Build Pipeline Overhaul

• Created scripts/build.ts - new build script that:
  • Bundles from src/entry.ts → dist/main.js using Bun
  • Applies minification and Node.js target
  • Adds executable shebang (#!/usr/bin/env node)
  • Externalizes heavy UI dependencies (keeps them out of bundle):
    • react, ink, ink-gradient, cfonts, ink-big-text
  • Runs TypeScript declaration generation after bundling
• Updated package.json build script to use new build pipeline

🚀 Bootstrap Entrypoint

• Created src/entry.ts - lightweight bootstrap that:
  • Sets process.noDeprecation = true before importing main module
  • Suppresses noisy Node.js deprecation warnings (e.g., punycode warnings from transitive deps)
  • Dynamically imports src/main.ts with error handling

🧹 Tooling & Config Improvements

• Updated ESLint config to type-check both tsconfig.json and tsconfig.build.json
• Added tsconfig.build.json for build scripts type-checking
• Removed legacy debug scripts (scripts/debug-keys.mjs, scripts/debug-parser.mjs)
• Added .agent/ to .gitignore

Bundle Size Impact

Result: ~50% reduction in bundle size

Why This Works:

1. Dependency Footprint Reduction: The monolithic googleapis package includes ALL Google APIs (~100+ services). By switching to scoped packages, we only bundle what we actually use (Gmail + Calendar APIs).
2. Externalized Dependencies: Heavy UI/runtime dependencies are marked as --external in the build, meaning they're not bundled into dist/main.js. They're still required at runtime (via node_modules), but the bundle itself is much smaller.

Behavior Changes / Notes

• Runtime Dependencies: The externalized UI dependencies (react, ink, etc.) must be present in node_modules at runtime. They're already declared in package.json dependencies, so normal installation (npm install, bun install) handles this automatically. Users don't need to install anything separately.
• Deprecation Warnings Suppressed: CLI startup will no longer emit Node.js DeprecationWarning output (including the noisy punycode warning from transitive dependencies on newer Node versions).

Risk Assessment

• Medium Risk: Google API client refactor could introduce subtle differences in OAuth client construction or API client initialization. Mitigated by existing comprehensive test coverage for Gmail/Calendar services.
• Low Risk: Build pipeline changes are mostly mechanical, but externalization means "missing dependency" errors would surface at runtime if installation is incomplete.

Test Plan

• ✅ Build Verification: Run bun run build and verify dist/main.js is generated with correct shebang
• ✅ Type Generation: Verify TypeScript declaration files are generated correctly
• ✅ CLI Smoke Test: Run bun run start (or node dist/main.js) and verify CLI starts without deprecation warnings
• ✅ Service Tests: Run existing Gmail/Calendar service tests to validate API client refactor works correctly