feat(settings): add /gsd:settings command for workflow toggles

Adds interactive settings command to toggle workflow agents:
- Plan Researcher (workflow.research)
- Plan Checker (workflow.plan_check)
- Execution Verifier (workflow.verifier)

Updates plan-phase.md and execute-phase.md to check config before
spawning these agents. Flags still override config per-invocation.

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

.planning/STATE.md

@@ -10,25 +10,25 @@ See: .planning/PROJECT.md (updated 2026-01-19)
 ## Current Position
 
 Phase: 2 of 3 (Context Injection)
-Plan: Not started
-Status: Ready to plan
-Last activity: 2026-01-20 — Phase 1 verified and complete
+Plan: 1 of 2 complete
+Status: In progress
+Last activity: 2026-01-20 — Completed 02-01-PLAN.md (Convention Detection Engine)
 
-Progress: [███░░░░░░░] 33%
+Progress: [████░░░░░░] 43%
 
 ## Performance Metrics
 
 **Velocity:**
-- Total plans completed: 2
-- Average duration: 3.5 min
-- Total execution time: 7 min
+- Total plans completed: 3
+- Average duration: 3.0 min
+- Total execution time: 9 min
 
 **By Phase:**
 
 | Phase | Plans | Total | Avg/Plan |
 |-------|-------|-------|----------|
 | 1. Foundation & Learning | 2/2 | 7 min | 3.5 min |
-| 2. Context Injection | 0/2 | - | - |
+| 2. Context Injection | 1/2 | 2 min | 2.0 min |
 | 3. Brownfield & Integration | 0/3 | - | - |
 
 *Updated after each plan completion*
@@ -45,6 +45,10 @@ Progress: [███░░░░░░░] 33%
 | Use heredoc for stdin testing | 01-02 | Pipe chaining has timing issues with async stdin |
 | Extract 'default' as export name | 01-02 | Both 'default' and identifier recorded for default exports |
 | Read file from disk for Edit tool | 01-02 | Edit only provides old_string/new_string, not full content |
+| Regenerate conventions every index update | 02-01 | Detection is fast, avoids staleness issues |
+| Skip 'default' in case detection | 02-01 | Keyword, not naming convention indicator |
+| Single lowercase words as camelCase | 02-01 | Follows camelCase rules (e.g., 'main', 'app') |
+| Use lookup tables for purposes | 02-01 | More maintainable than regex patterns |
 
 ### Pending Todos
 
@@ -57,5 +61,5 @@ Progress: [███░░░░░░░] 33%
 ## Session Continuity
 
 Last session: 2026-01-20
-Stopped at: Phase 1 verified and complete, ready for Phase 2
+Stopped at: Completed 02-01-PLAN.md, ready for 02-02-PLAN.md
 Resume file: None