* feat(commands): add external plan import command /gsd-import
Adds a new /gsd-import command for importing external plan files into
the GSD planning system with conflict detection against PROJECT.md
decisions and CONTEXT.md locked decisions.
Scoped to --from mode only (plan file import). Uses validatePath()
from security.cjs for file path validation. Surfaces all conflicts
before writing and never auto-resolves. Handles missing PROJECT.md
gracefully by skipping constraint checks.
--prd mode (PRD extraction) is noted as future work.
Closes#1731
* fix(commands): address review feedback for /gsd-import
- Add structural tests for command/workflow files (13 assertions)
- Add REQUIREMENTS.md to conflict detection context loading
- Replace security.cjs CLI invocation with inline path validation
- Move PBR naming check from blocker list to conversion step
- Add Edit to allowed-tools for ROADMAP.md/STATE.md patching
- Remove emoji from completion banner and validation message
