c48d2e6080
- Canonicalized file and CLI defaults from `read` to `open` across tool registration and prompts. - Added `resolveToolAlias()` and applied alias-normalized tool selection so legacy `read` maps to `open`. - Updated runtime, UI, and export layers to treat `open` as first-class while preserving `read` compatibility. - Renamed read prompt docs to `open.md`/`open-chunk.md` and refreshed system guidance to recommend `open`. - Updated tool-related tests and expectations from `read` to `open` (including test fixtures and aliases).