gsd-execute-phase

<objective> Execute all plans in a phase using wave-based parallel execution. Orchestrator stays lean: discover plans, analyze dependencies, group into waves, spawn subagents, collect results. Each subagent loads the full execute-plan context and handles its own plan. Optional wave filter: - `--wave N` executes only Wave `N` for pacing, quota management, or staged rollout - phase verification/completion still only happens when no incomplete plans remain after the selected wave finishes Flag handling rule: - The optional flags documented below are available behaviors, not implied active behaviors - A flag is active only when its literal token appears in `$ARGUMENTS` - If a documented flag is absent from `$ARGUMENTS`, treat it as inactive Context budget: ~15% orchestrator, 100% fresh per subagent. </objective> <execution_context> @~/.claude/gsd-core/workflows/execute-phase.md @~/.claude/gsd-core/references/ui-brand.md </execution_context> <runtime_note> **Copilot (VS Code):** Use `vscode_askquestions` wherever this workflow calls `AskUserQuestion`. They are equivalent — `vscode_askquestions` is the VS Code Copilot implementation of the same interactive question API. </runtime_note> <context> Phase: $ARGUMENTS **Available optional flags (documentation only — not automatically active):** - `--wave N` — Execute only Wave `N` in the phase. Use when you want to pace execution or stay inside usage limits. - `--gaps-only` — Execute only gap closure plans (plans with `gap_closu...