fix(research-phase): remove domain gatekeeping

The when_to_use section was overly restrictive, refusing research
for "standard" domains. Research benefits any unfamiliar territory,
not just niche technical domains.

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

commands/gsd/research-phase.md

@@ -68,23 +68,6 @@ Check for `.planning/phases/XX-name/{phase}-CONTEXT.md` - bonus context from dis
 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