feat: unified task.json schema migration and multi-module updates

- Create task-schema.json (JSON Schema draft-07) with 10 field blocks fusing
  Unified JSONL, 6-field Task JSON, and Solution Schema advantages
- Migrate unified-execute-with-file from JSONL to .task/*.json directory scanning
- Migrate 3 producers (lite-plan, plan-converter, collaborative-plan) to
  .task/*.json multi-file output
- Add review-cycle Phase 7.5 export-to-tasks (FIX-*.json) and issue-resolve
  --export-tasks option
- Add schema compatibility annotations to action-planning-agent, workflow-plan,
  and tdd-plan
- Add spec-generator skill phases and templates
- Add memory v2 pipeline (consolidation, extraction, job scheduler, embedder)
- Add secret-redactor utility and core-memory enhancements
- Add codex-lens accuracy benchmarks and staged env config overrides

.claude/skills/spec-generator/README.md

@@ -0,0 +1,81 @@
+# Spec Generator
+
+Structured specification document generator producing a complete document chain (Product Brief -> PRD -> Architecture -> Epics).
+
+## Usage
+
+```bash
+# Via workflow command
+/workflow:spec "Build a task management system"
+/workflow:spec -y "User auth with OAuth2"    # Auto mode
+/workflow:spec -c "task management"           # Resume session
+```
+
+## Architecture
+
+```
+spec-generator/
+|- SKILL.md                          # Entry point: metadata + architecture + flow
+|- phases/
+|  |- 01-discovery.md                # Seed analysis + codebase exploration
+|  |- 02-product-brief.md            # Multi-CLI product brief generation
+|  |- 03-requirements.md             # PRD with MoSCoW priorities
+|  |- 04-architecture.md             # Architecture decisions + review
+|  |- 05-epics-stories.md            # Epic/Story decomposition
+|  |- 06-readiness-check.md          # Quality validation + handoff
+|- specs/
+|  |- document-standards.md          # Format, frontmatter, naming rules
+|  |- quality-gates.md               # Per-phase quality criteria
+|- templates/
+|  |- product-brief.md               # Product brief template
+|  |- requirements-prd.md            # PRD template
+|  |- architecture-doc.md            # Architecture document template
+|  |- epics-template.md              # Epic/Story template
+|- README.md                         # This file
+```
+
+## 6-Phase Pipeline
+
+| Phase | Name | Output | CLI Tools |
+|-------|------|--------|-----------|
+| 1 | Discovery | spec-config.json | Gemini (analysis) |
+| 2 | Product Brief | product-brief.md | Gemini + Codex + Claude (parallel) |
+| 3 | Requirements | requirements.md | Gemini (analysis) |
+| 4 | Architecture | architecture.md | Gemini + Codex (sequential) |
+| 5 | Epics & Stories | epics.md | Gemini (analysis) |
+| 6 | Readiness Check | readiness-report.md, spec-summary.md | Gemini (validation) |
+
+## Runtime Output
+
+```
+.workflow/.spec/SPEC-{slug}-{YYYY-MM-DD}/
+|- spec-config.json              # Session state
+|- discovery-context.json        # Codebase context (optional)
+|- product-brief.md              # Phase 2
+|- requirements.md               # Phase 3
+|- architecture.md               # Phase 4
+|- epics.md                      # Phase 5
+|- readiness-report.md           # Phase 6
+|- spec-summary.md               # Phase 6
+```
+
+## Flags
+
+- `-y|--yes`: Auto mode - skip all interactive confirmations
+- `-c|--continue`: Resume from last completed phase
+
+## Handoff
+
+After Phase 6, choose execution path:
+- `workflow:lite-plan` - Execute per Epic
+- `workflow:req-plan-with-file` - Roadmap decomposition
+- `workflow:plan` - Full planning
+- `issue:new` - Create issues per Epic
+
+## Design Principles
+
+- **Document chain**: Each phase builds on previous outputs
+- **Multi-perspective**: Gemini/Codex/Claude provide different viewpoints
+- **Template-driven**: Consistent format via templates + frontmatter
+- **Resumable**: spec-config.json tracks completed phases
+- **Pure documentation**: No code generation - clean handoff to execution workflows