feat(01-01): create quick.md command file with structure

- Add frontmatter with name, description, allowed-tools
- Include objective explaining quick mode purpose
- Add process section with steps 1-7 (orchestration deferred to Plan 02)
- Include success criteria for full quick task flow

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

commands/gsd/quick.md

@@ -0,0 +1,145 @@
+---
+name: gsd:quick
+description: Execute a quick task with GSD guarantees (atomic commits, state tracking) but skip optional agents
+argument-hint: ""
+allowed-tools:
+  - Read
+  - Write
+  - Edit
+  - Glob
+  - Grep
+  - Bash
+  - Task
+  - AskUserQuestion
+---
+
+<objective>
+Execute small, ad-hoc tasks with GSD guarantees (atomic commits, STATE.md tracking) while skipping optional agents (research, plan-checker, verifier).
+
+Quick mode is the same system with a shorter path:
+- Spawns gsd-planner (quick mode) + gsd-executor(s)
+- Skips gsd-phase-researcher, gsd-plan-checker, gsd-verifier
+- Quick tasks live in `.planning/quick/` separate from planned phases
+- Updates STATE.md "Quick Tasks Completed" table (NOT ROADMAP.md)
+
+Use when: You know exactly what to do and the task is small enough to not need research or verification.
+</objective>
+
+<execution_context>
+<!-- DEFERRED TO PLAN 02: Reference to quick workflow will be populated here -->
+</execution_context>
+
+<context>
+@.planning/STATE.md
+</context>
+
+<process>
+**Step 1: Pre-flight validation**
+
+Check that an active GSD project exists:
+
+```bash
+if [ ! -f .planning/ROADMAP.md ]; then
+  echo "Quick mode requires an active project with ROADMAP.md."
+  echo "Run /gsd:new-project first."
+  exit 1
+fi
+```
+
+If validation fails, stop immediately with the error message.
+
+Quick tasks can run mid-phase - validation only checks ROADMAP.md exists, not phase status.
+
+---
+
+**Step 2: Get task description**
+
+Prompt user interactively for the task description:
+
+```
+AskUserQuestion(
+  header: "Quick Task",
+  question: "What do you want to do?",
+  followUp: null
+)
+```
+
+Store response as `$DESCRIPTION`.
+
+If empty, re-prompt: "Please provide a task description."
+
+Generate slug from description:
+```bash
+slug=$(echo "$DESCRIPTION" | tr '[:upper:]' '[:lower:]' | sed 's/[^a-z0-9]/-/g' | sed 's/--*/-/g' | sed 's/^-//;s/-$//' | cut -c1-40)
+```
+
+---
+
+**Step 3: Calculate next quick task number**
+
+Ensure `.planning/quick/` directory exists and find the next sequential number:
+
+```bash
+# Ensure .planning/quick/ exists
+mkdir -p .planning/quick
+
+# Find highest existing number and increment
+last=$(ls -1d .planning/quick/[0-9][0-9][0-9]-* 2>/dev/null | sort -r | head -1 | xargs -I{} basename {} | grep -oE '^[0-9]+')
+
+if [ -z "$last" ]; then
+  next_num="001"
+else
+  next_num=$(printf "%03d" $((10#$last + 1)))
+fi
+```
+
+---
+
+**Step 4: Create quick task directory**
+
+Create the directory for this quick task:
+
+```bash
+QUICK_DIR=".planning/quick/${next_num}-${slug}"
+mkdir -p "$QUICK_DIR"
+```
+
+Report to user:
+```
+Creating quick task ${next_num}: ${DESCRIPTION}
+Directory: ${QUICK_DIR}
+```
+
+Store `$QUICK_DIR` for use in orchestration.
+
+---
+
+**Step 5: Orchestration (spawn planner and executor)**
+
+<!-- DEFERRED TO PLAN 02: Planner spawning, executor spawning, wave execution, STATE.md updates, commits -->
+
+---
+
+**Step 6: Update STATE.md**
+
+<!-- DEFERRED TO PLAN 02: Add row to "Quick Tasks Completed" table -->
+
+---
+
+**Step 7: Commit artifacts**
+
+<!-- DEFERRED TO PLAN 02: Stage and commit quick task artifacts -->
+
+</process>
+
+<success_criteria>
+- [ ] ROADMAP.md validation passes
+- [ ] User provides task description
+- [ ] Slug generated (lowercase, hyphens, max 40 chars)
+- [ ] Next number calculated (001, 002, 003...)
+- [ ] Directory created at `.planning/quick/NNN-slug/`
+- [ ] PLAN.md created by planner
+- [ ] SUMMARY.md created by executor
+- [ ] STATE.md updated with quick task row
+- [ ] Artifacts committed
+</success_criteria>