gsd-phase

<objective> Manage phases in ROADMAP.md with a single consolidated command. Mode routing: - **default** (no flag): Add a new integer phase to the end of the current milestone → add-phase workflow - **--insert**: Insert urgent work as a decimal phase (e.g., 72.1) between existing phases → insert-phase workflow - **--remove**: Remove a future phase and renumber subsequent phases → remove-phase workflow - **--edit**: Edit any field of an existing phase in place → edit-phase workflow </objective> <routing> | Flag | Action | Workflow | |------|--------|----------| | (none) | Add new integer phase at end of milestone | add-phase | | --insert | Insert decimal phase (e.g., 72.1) after specified phase | insert-phase | | --remove | Remove future phase, renumber subsequent | remove-phase | | --edit | Edit fields of existing phase in place | edit-phase | </routing> <execution_context> @~/.claude/gsd-core/workflows/add-phase.md @~/.claude/gsd-core/workflows/insert-phase.md @~/.claude/gsd-core/workflows/remove-phase.md @~/.claude/gsd-core/workflows/edit-phase.md </execution_context> <context> Arguments: $ARGUMENTS Parse the first token of $ARGUMENTS: - If it is `--insert`: strip the flag, pass remainder (format: <after-phase-number> <description>) to insert-phase workflow - If it is `--remove`: strip the flag, pass remainder (phase number) to remove-phase workflow - If it is `--edit`: strip the flag, pass remainder (phase-number [--force]) to edit-phase workflow - Otherwise: pass al...