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/code-review.md

@@ -1,68 +0,0 @@
----
-description: Review code for quality, security, and maintainability
-agent: code-reviewer
-subtask: true
----
-
-# Code Review Command
-
-Review code changes for quality, security, and maintainability: $ARGUMENTS
-
-## Your Task
-
-1. **Get changed files**: Run `git diff --name-only HEAD`
-2. **Analyze each file** for issues
-3. **Generate structured report**
-4. **Provide actionable recommendations**
-
-## Check Categories
-
-### Security Issues (CRITICAL)
-- [ ] Hardcoded credentials, API keys, tokens
-- [ ] SQL injection vulnerabilities
-- [ ] XSS vulnerabilities
-- [ ] Missing input validation
-- [ ] Insecure dependencies
-- [ ] Path traversal risks
-- [ ] Authentication/authorization flaws
-
-### Code Quality (HIGH)
-- [ ] Functions > 50 lines
-- [ ] Files > 800 lines
-- [ ] Nesting depth > 4 levels
-- [ ] Missing error handling
-- [ ] console.log statements
-- [ ] TODO/FIXME comments
-- [ ] Missing JSDoc for public APIs
-
-### Best Practices (MEDIUM)
-- [ ] Mutation patterns (use immutable instead)
-- [ ] Unnecessary complexity
-- [ ] Missing tests for new code
-- [ ] Accessibility issues (a11y)
-- [ ] Performance concerns
-
-### Style (LOW)
-- [ ] Inconsistent naming
-- [ ] Missing type annotations
-- [ ] Formatting issues
-
-## Report Format
-
-For each issue found:
-
-```
-**[SEVERITY]** file.ts:123
-Issue: [Description]
-Fix: [How to fix]
-```
-
-## Decision
-
-- **CRITICAL or HIGH issues**: Block commit, require fixes
-- **MEDIUM issues**: Recommend fixes before merge
-- **LOW issues**: Optional improvements
-
----
-
-**IMPORTANT**: Never approve code with security vulnerabilities!