Adds /gsd:add-todo and /gsd:check-todos commands for capturing
ideas during work sessions without losing context.
Features:
- Capture todos from conversation context or explicit description
- Structured frontmatter (created, title, area, files)
- Area inference from file paths for grouping
- Duplicate detection before creating
- Filter todos by area
- Route to appropriate action (work now, add to phase, brainstorm)
- Git commits on capture and when starting work
Closes#48
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>