refactor: replace Task tool with Agent tool and fix schema compliance

## Task -> Agent Replacement
- Replace all Task({}) calls with Agent({}) across .claude/ directory
- Update allowed-tools declarations from Task to Agent
- Update documentation references from "Task tool" to "Agent tool"

## Schema Compliance Fixes

### Agent Schema
- Add missing required `description` parameter in 6 files
- Add missing `run_in_background: false` for subagent calls
- Add missing `subagent_type` parameter

### AskUserQuestion Schema
- Fix issue-manage/SKILL.md: reduce options from 5 to 4 (max allowed)

### SendMessage Schema
- Fix team-worker.md: use correct params (type, content, summary)
- Remove invalid `team_name` parameter

### TaskCreate/TaskUpdate Schema
- Remove invalid `blockedBy`, `owner`, `status` from TaskCreate calls
- Use separate TaskUpdate calls for dependencies and ownership
- Fix TaskUpdate syntax to use object parameter

### TeamDelete Schema
- Remove parameters from TeamDelete() calls (should be no params)

### TaskOutput Schema
- Fix Python-style syntax to JavaScript object syntax

## Files Changed
- 146 files updated across commands/, skills/, skills_lib/, agents/

.claude/skills/team-lifecycle/role-specs/executor.md

@@ -42,7 +42,7 @@ message_types:
 
 | Backend | Invocation | Use Case |
 |---------|-----------|----------|
-| agent | `Task({ subagent_type: "code-developer", run_in_background: false })` | Simple, direct edits |
+| agent | `Agent({ subagent_type: "code-developer", run_in_background: false })` | Simple, direct edits |
 | codex | `ccw cli --tool codex --mode write` (background) | Complex, architecture |
 | gemini | `ccw cli --tool gemini --mode write` (background) | Analysis-heavy |