feat(gsd): add research-phase for niche domain ecosystem discovery

- Add /gsd:research-phase command for comprehensive ecosystem research
- Rename FINDINGS.md → DISCOVERY.md for clarity
- Rename research-phase.md → discovery-phase.md (shallow "which library")
- New research-phase.md for deep "how experts build this" research
- Creates RESEARCH.md with stack, patterns, pitfalls, don't-hand-roll
- plan-phase loads RESEARCH.md when present

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

commands/gsd/help.md

@@ -55,6 +55,16 @@ Gather phase context through adaptive questioning before planning.
 
 Usage: `/gsd:discuss-phase 2`
 
+**`/gsd:research-phase <number>`**
+Comprehensive ecosystem research for niche/complex domains.
+
+- Discovers standard stack, architecture patterns, pitfalls
+- Creates RESEARCH.md with "how experts build this" knowledge
+- Use for 3D, games, audio, shaders, ML, and other specialized domains
+- Goes beyond "which library" to ecosystem knowledge
+
+Usage: `/gsd:research-phase 3`
+
 **`/gsd:list-phase-assumptions <number>`**
 Surface Claude's assumptions about a phase before planning.
 
@@ -236,6 +246,15 @@ Change anytime by editing `.planning/config.json`
 /gsd:execute-plan .planning/phases/01-foundation/01-01-PLAN.md
 ```
 
+**Building something in a niche domain (3D, games, audio, shaders):**
+
+```
+/gsd:new-project
+/gsd:research-phase 1  # Learn how experts build this
+/gsd:plan-phase 1      # Plan using research findings
+/gsd:execute-plan .planning/phases/01-foundation/01-01-PLAN.md
+```
+
 **Resuming work after a break:**
 
 ```

commands/gsd/research-phase.md

@@ -0,0 +1,90 @@
+---
+description: Research how to implement a phase before planning
+argument-hint: "[phase]"
+allowed-tools:
+  - Read
+  - Bash
+  - Glob
+  - Grep
+  - Write
+  - WebFetch
+  - WebSearch
+  - mcp__context7__*
+---
+
+<objective>
+Comprehensive research on HOW to implement a phase before planning.
+
+This is for niche/complex domains where Claude's training data is sparse or outdated. Research discovers:
+- What libraries exist for this problem
+- What architecture patterns experts use
+- What the standard stack looks like
+- What problems people commonly hit
+- What NOT to hand-roll (use existing solutions)
+
+Output: RESEARCH.md with ecosystem knowledge that informs quality planning.
+</objective>
+
+<execution_context>
+@~/.claude/get-shit-done/workflows/research-phase.md
+@~/.claude/get-shit-done/templates/research.md
+@~/.claude/get-shit-done/references/research-pitfalls.md
+</execution_context>
+
+<context>
+Phase number: $ARGUMENTS (required)
+
+**Load project state:**
+@.planning/STATE.md
+
+**Load roadmap:**
+@.planning/ROADMAP.md
+
+**Load phase context if exists:**
+Check for `.planning/phases/XX-name/{phase}-CONTEXT.md` - bonus context from discuss-phase.
+</context>
+
+<process>
+1. Validate phase number argument (error if missing or invalid)
+2. Check if phase exists in roadmap - extract phase description
+3. Check if RESEARCH.md already exists (offer to update or use existing)
+4. Load CONTEXT.md if it exists (bonus context for research direction)
+5. Follow research-phase.md workflow:
+   - Analyze phase to identify knowledge gaps
+   - Determine research domains (architecture, ecosystem, patterns, pitfalls)
+   - Execute comprehensive research via Context7, official docs, WebSearch
+   - Cross-verify all findings
+   - Create RESEARCH.md with actionable ecosystem knowledge
+6. Offer next steps (plan the phase)
+</process>
+
+<when_to_use>
+**Use research-phase for:**
+- 3D graphics (Three.js, WebGL, procedural generation)
+- Game development (physics, collision, AI, procedural content)
+- Audio/music (Web Audio API, DSP, synthesis)
+- Shaders (GLSL, Metal, ISF)
+- ML/AI integration (model serving, inference, pipelines)
+- Real-time systems (WebSockets, WebRTC, sync)
+- Specialized frameworks with active ecosystems
+- Any domain where "how do experts do this" matters
+
+**Skip research-phase for:**
+- Standard web dev (auth, CRUD, REST APIs)
+- Well-known patterns (forms, validation, testing)
+- Simple integrations (Stripe, SendGrid with clear docs)
+- Commodity features Claude handles well
+</when_to_use>
+
+<success_criteria>
+- [ ] Phase validated against roadmap
+- [ ] Domain/ecosystem identified from phase description
+- [ ] Comprehensive research executed (Context7 + official docs + WebSearch)
+- [ ] All WebSearch findings cross-verified with authoritative sources
+- [ ] RESEARCH.md created with ecosystem knowledge
+- [ ] Standard stack/libraries identified
+- [ ] Architecture patterns documented
+- [ ] Common pitfalls catalogued
+- [ ] What NOT to hand-roll is clear
+- [ ] User knows next steps (plan phase)
+</success_criteria>