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.

.cursor/rules/hooks-guidance.md

@@ -1,36 +0,0 @@
----
-description: "Guidance on achieving hook-like functionality in Cursor IDE"
-alwaysApply: false
----
-
-# Hooks Guidance for Cursor
-
-Cursor does not have a native hooks system like Claude Code's PreToolUse/PostToolUse/Stop hooks. However, you can achieve similar automation through:
-
-## Formatting on Save
-
-Configure your editor settings to run formatters on save:
-- **TypeScript/JavaScript**: Prettier, ESLint with `--fix`
-- **Python**: Black, Ruff
-- **Go**: gofmt, goimports
-
-## Linting Integration
-
-Use Cursor's built-in linter support:
-- ESLint for TypeScript/JavaScript
-- Ruff/Flake8 for Python
-- golangci-lint for Go
-
-## Pre-Commit Hooks
-
-Use git pre-commit hooks (via tools like `husky` or `pre-commit`) for:
-- Running formatters before commit
-- Checking for console.log/print statements
-- Running type checks
-- Validating no hardcoded secrets
-
-## CI/CD Checks
-
-For checks that ran as Stop hooks in Claude Code:
-- Add them to your CI/CD pipeline instead
-- GitHub Actions, GitLab CI, etc.