## Summary
- Add `DyadError` / `DyadErrorKind` in `src/errors/dyad_error.ts` for
classified failures (validation, not found, auth, precondition,
conflict, user cancel, rate limit, etc.).
- Extend `shouldFilterTelemetryException` so filtered kinds are not sent
as PostHog `$exception` events; preserve legacy filters (RateLimitError
429, exact Supabase message set).
- `safe_handle` rethrows `DyadError` unchanged; typed handler invalid
input uses `Validation`.
- Migrate many IPC/main/git/supabase/local-agent call sites from `throw
new Error` to `DyadError` with appropriate kinds.
- Document in `AGENTS.md`, `rules/dyad-errors.md`, and
`.cursor/rules/ipc.mdc`.

## Test plan
- `npm run ts`, `npm run lint`, `npm test` (946 tests) passed locally.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Made with [Cursor](https://cursor.com)
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