feat(ecc): prune plugin 43→12 items, promote 7 rules to .claude/rules/ (#245)

ECC community plugin pruning: removed 530+ non-essential files
(.cursor/, .opencode/, docs/ja-JP, docs/zh-CN, docs/zh-TW,
language-specific skills/agents/rules). Retained 4 agents,
3 commands, 5 skills. Promoted 13 rule files (8 common + 5
typescript) to .claude/rules/ for CC native loading. Extracted
reusable patterns to EXTRACTED-PATTERNS.md.

.opencode/commands/orchestrate.md

@@ -1,88 +0,0 @@
----
-description: Orchestrate multiple agents for complex tasks
-agent: planner
-subtask: true
----
-
-# Orchestrate Command
-
-Orchestrate multiple specialized agents for this complex task: $ARGUMENTS
-
-## Your Task
-
-1. **Analyze task complexity** and break into subtasks
-2. **Identify optimal agents** for each subtask
-3. **Create execution plan** with dependencies
-4. **Coordinate execution** - parallel where possible
-5. **Synthesize results** into unified output
-
-## Available Agents
-
-| Agent | Specialty | Use For |
-|-------|-----------|---------|
-| planner | Implementation planning | Complex feature design |
-| architect | System design | Architectural decisions |
-| code-reviewer | Code quality | Review changes |
-| security-reviewer | Security analysis | Vulnerability detection |
-| tdd-guide | Test-driven dev | Feature implementation |
-| build-error-resolver | Build fixes | TypeScript/build errors |
-| e2e-runner | E2E testing | User flow testing |
-| doc-updater | Documentation | Updating docs |
-| refactor-cleaner | Code cleanup | Dead code removal |
-| go-reviewer | Go code | Go-specific review |
-| go-build-resolver | Go builds | Go build errors |
-| database-reviewer | Database | Query optimization |
-
-## Orchestration Patterns
-
-### Sequential Execution
-```
-planner → tdd-guide → code-reviewer → security-reviewer
-```
-Use when: Later tasks depend on earlier results
-
-### Parallel Execution
-```
-┌→ security-reviewer
-planner →├→ code-reviewer
-└→ architect
-```
-Use when: Tasks are independent
-
-### Fan-Out/Fan-In
-```
-         ┌→ agent-1 ─┐
-planner →├→ agent-2 ─┼→ synthesizer
-         └→ agent-3 ─┘
-```
-Use when: Multiple perspectives needed
-
-## Execution Plan Format
-
-### Phase 1: [Name]
-- Agent: [agent-name]
-- Task: [specific task]
-- Depends on: [none or previous phase]
-
-### Phase 2: [Name] (parallel)
-- Agent A: [agent-name]
-  - Task: [specific task]
-- Agent B: [agent-name]
-  - Task: [specific task]
-- Depends on: Phase 1
-
-### Phase 3: Synthesis
-- Combine results from Phase 2
-- Generate unified output
-
-## Coordination Rules
-
-1. **Plan before execute** - Create full execution plan first
-2. **Minimize handoffs** - Reduce context switching
-3. **Parallelize when possible** - Independent tasks in parallel
-4. **Clear boundaries** - Each agent has specific scope
-5. **Single source of truth** - One agent owns each artifact
-
----
-
-**NOTE**: Complex tasks benefit from multi-agent orchestration. Simple tasks should use single agents directly.