Refactor workflow session commands to utilize ccw CLI for session management

- Updated session completion process to use `ccw session` commands for listing, reading, and updating session statuses.
- Enhanced session listing command to provide metadata and statistics using `ccw session list` and `ccw session stats`.
- Streamlined session resume functionality with `ccw session` commands for checking status and updating session state.
- Improved session creation process by replacing manual directory and metadata handling with `ccw session init`.
- Introduced `session_manager` tool for simplified session operations, including listing, updating, and archiving sessions.
- Updated conflict resolution tools to generate structured output in `conflict-resolution.json` instead of markdown files.
- Enhanced TDD and UI design tools to utilize `ccw cli exec` for executing analysis commands, improving integration with the workflow.

.claude/skills/command-guide/reference/commands/workflow/tdd-plan.md

@@ -164,10 +164,10 @@ SlashCommand(command="/workflow:tools:conflict-resolution --session [sessionId]
 
 **Parse Output**:
 - Extract: Execution status (success/skipped/failed)
-- Verify: CONFLICT_RESOLUTION.md file path (if executed)
+- Verify: conflict-resolution.json file path (if executed)
 
 **Validation**:
-- File `.workflow/active/[sessionId]/.process/CONFLICT_RESOLUTION.md` exists (if executed)
+- File `.workflow/active/[sessionId]/.process/conflict-resolution.json` exists (if executed)
 
 **Skip Behavior**:
 - If conflict_risk is "none" or "low", skip directly to Phase 5
@@ -402,7 +402,7 @@ TDD Workflow Orchestrator
 │     ├─ Phase 4.1: Detect conflicts with CLI
 │     ├─ Phase 4.2: Present conflicts to user
 │     └─ Phase 4.3: Apply resolution strategies
-│     └─ Returns: CONFLICT_RESOLUTION.md              ← COLLAPSED
+│     └─ Returns: conflict-resolution.json            ← COLLAPSED
 │  ELSE:
 │  └─ Skip to Phase 5
 │