feat(agents): add skills frontmatter and hooks examples to all agents

Add skills: field to all 11 agent frontmatter files with forward-compatible
GSD workflow skill references (silently ignored until skill files are created).

Add commented hooks: examples to 9 file-writing agents showing PostToolUse
hook syntax for project-specific linting/formatting. Read-only agents
(plan-checker, integration-checker) skip hooks as they cannot modify files.

Per Claude Code docs: subagents don't inherit skills or hooks from the
parent conversation — they must be explicitly listed in frontmatter.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

agents/gsd-codebase-mapper.md

@@ -3,6 +3,14 @@ name: gsd-codebase-mapper
 description: Explores codebase and writes structured analysis documents. Spawned by map-codebase with a focus area (tech, arch, quality, concerns). Writes documents directly to reduce orchestrator context load.
 tools: Read, Bash, Grep, Glob, Write
 color: cyan
+skills:
+  - gsd-mapper-workflow
+# hooks:
+#   PostToolUse:
+#     - matcher: "Write|Edit"
+#       hooks:
+#         - type: command
+#           command: "npx eslint --fix $FILE 2>/dev/null || true"
 ---
 
 <role>

agents/gsd-debugger.md

@@ -3,6 +3,14 @@ name: gsd-debugger
 description: Investigates bugs using scientific method, manages debug sessions, handles checkpoints. Spawned by /gsd:debug orchestrator.
 tools: Read, Write, Edit, Bash, Grep, Glob, WebSearch
 color: orange
+skills:
+  - gsd-debugger-workflow
+# hooks:
+#   PostToolUse:
+#     - matcher: "Write|Edit"
+#       hooks:
+#         - type: command
+#           command: "npx eslint --fix $FILE 2>/dev/null || true"
 ---
 
 <role>

agents/gsd-executor.md

@@ -3,6 +3,14 @@ name: gsd-executor
 description: Executes GSD plans with atomic commits, deviation handling, checkpoint protocols, and state management. Spawned by execute-phase orchestrator or execute-plan command.
 tools: Read, Write, Edit, Bash, Grep, Glob
 color: yellow
+skills:
+  - gsd-executor-workflow
+# hooks:
+#   PostToolUse:
+#     - matcher: "Write|Edit"
+#       hooks:
+#         - type: command
+#           command: "npx eslint --fix $FILE 2>/dev/null || true"
 ---
 
 <role>

agents/gsd-integration-checker.md

@@ -3,6 +3,8 @@ name: gsd-integration-checker
 description: Verifies cross-phase integration and E2E flows. Checks that phases connect properly and user workflows complete end-to-end.
 tools: Read, Bash, Grep, Glob
 color: blue
+skills:
+  - gsd-integration-workflow
 ---
 
 <role>

agents/gsd-phase-researcher.md

@@ -3,6 +3,14 @@ name: gsd-phase-researcher
 description: Researches how to implement a phase before planning. Produces RESEARCH.md consumed by gsd-planner. Spawned by /gsd:plan-phase orchestrator.
 tools: Read, Write, Bash, Grep, Glob, WebSearch, WebFetch, mcp__context7__*
 color: cyan
+skills:
+  - gsd-researcher-workflow
+# hooks:
+#   PostToolUse:
+#     - matcher: "Write|Edit"
+#       hooks:
+#         - type: command
+#           command: "npx eslint --fix $FILE 2>/dev/null || true"
 ---
 
 <role>

agents/gsd-plan-checker.md

@@ -3,6 +3,8 @@ name: gsd-plan-checker
 description: Verifies plans will achieve phase goal before execution. Goal-backward analysis of plan quality. Spawned by /gsd:plan-phase orchestrator.
 tools: Read, Bash, Glob, Grep
 color: green
+skills:
+  - gsd-plan-checker-workflow
 ---
 
 <role>

agents/gsd-planner.md

@@ -3,6 +3,14 @@ name: gsd-planner
 description: Creates executable phase plans with task breakdown, dependency analysis, and goal-backward verification. Spawned by /gsd:plan-phase orchestrator.
 tools: Read, Write, Bash, Glob, Grep, WebFetch, mcp__context7__*
 color: green
+skills:
+  - gsd-planner-workflow
+# hooks:
+#   PostToolUse:
+#     - matcher: "Write|Edit"
+#       hooks:
+#         - type: command
+#           command: "npx eslint --fix $FILE 2>/dev/null || true"
 ---
 
 <role>

agents/gsd-project-researcher.md

@@ -3,6 +3,14 @@ name: gsd-project-researcher
 description: Researches domain ecosystem before roadmap creation. Produces files in .planning/research/ consumed during roadmap creation. Spawned by /gsd:new-project or /gsd:new-milestone orchestrators.
 tools: Read, Write, Bash, Grep, Glob, WebSearch, WebFetch, mcp__context7__*
 color: cyan
+skills:
+  - gsd-researcher-workflow
+# hooks:
+#   PostToolUse:
+#     - matcher: "Write|Edit"
+#       hooks:
+#         - type: command
+#           command: "npx eslint --fix $FILE 2>/dev/null || true"
 ---
 
 <role>

agents/gsd-research-synthesizer.md

@@ -3,6 +3,14 @@ name: gsd-research-synthesizer
 description: Synthesizes research outputs from parallel researcher agents into SUMMARY.md. Spawned by /gsd:new-project after 4 researcher agents complete.
 tools: Read, Write, Bash
 color: purple
+skills:
+  - gsd-synthesizer-workflow
+# hooks:
+#   PostToolUse:
+#     - matcher: "Write|Edit"
+#       hooks:
+#         - type: command
+#           command: "npx eslint --fix $FILE 2>/dev/null || true"
 ---
 
 <role>

agents/gsd-roadmapper.md

@@ -3,6 +3,14 @@ name: gsd-roadmapper
 description: Creates project roadmaps with phase breakdown, requirement mapping, success criteria derivation, and coverage validation. Spawned by /gsd:new-project orchestrator.
 tools: Read, Write, Bash, Glob, Grep
 color: purple
+skills:
+  - gsd-roadmapper-workflow
+# hooks:
+#   PostToolUse:
+#     - matcher: "Write|Edit"
+#       hooks:
+#         - type: command
+#           command: "npx eslint --fix $FILE 2>/dev/null || true"
 ---
 
 <role>

agents/gsd-verifier.md

@@ -3,6 +3,14 @@ name: gsd-verifier
 description: Verifies phase goal achievement through goal-backward analysis. Checks codebase delivers what phase promised, not just that tasks completed. Creates VERIFICATION.md report.
 tools: Read, Write, Bash, Grep, Glob
 color: green
+skills:
+  - gsd-verifier-workflow
+# hooks:
+#   PostToolUse:
+#     - matcher: "Write|Edit"
+#       hooks:
+#         - type: command
+#           command: "npx eslint --fix $FILE 2>/dev/null || true"
 ---
 
 <role>