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/workflow-plan/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: workflow-plan
 description: Unified planning skill - 4-phase planning workflow, plan verification, and interactive replanning. Triggers on "workflow-plan", "workflow-plan-verify", "workflow:replan".
-allowed-tools: Skill, Task, AskUserQuestion, TodoWrite, Read, Write, Edit, Bash, Glob, Grep
+allowed-tools: Skill, Agent, AskUserQuestion, TodoWrite, Read, Write, Edit, Bash, Glob, Grep
 ---
 
 # Workflow Plan

.claude/skills/workflow-plan/phases/03-conflict-resolution.md

@@ -194,7 +194,7 @@ FOR each conflict:
       }
 
       // 5. Agent re-analysis
-      reanalysisResult = Task({
+      reanalysisResult = Agent({
         subagent_type: "cli-execution-agent",
         run_in_background: false,
         prompt: `Conflict: ${conflict.id}, Strategy: ${selectedStrategy.name}