feat(web): add browser launch and database access

[skulidropek]

Summary

• Add docker-git browser / docker-git web flow that bootstraps the controller, builds the browser frontend, and serves it with the resolved API URL.
• Add database discovery/proxy API and web panels for project database access.
• Keep browser actions gated by available Playwright sidecar state and preserve URL-driven web navigation.

Mathematical guarantees

• Invariant: browser frontend API requests resolve through the selected controller endpoint, not a stale Docker IP.
• Invariant: database/browser actions are available only from decoded project capability state.
• Invariant: CLI command routing remains exhaustive through the Command union.

Verification

• bun run --cwd packages/api typecheck
• bun run --cwd packages/api lint
• bun run --cwd packages/api test -- project-port-forward-core.test.ts schema.test.ts
• bun run --cwd packages/app typecheck
• bun run --cwd packages/app lint
• bun run --cwd packages/app test -- parser-browser.test.ts program.test.ts controller.test.ts app-ready-shortcuts.test.ts app-ready-url.test.ts
• DOCKER_GIT_WEB_PORT=4184 bun run docker-git browser smoke: / returned 200 text/html, /api/health returned ok