v6.2.0: Refactor musubi-init.js to meet complexity limits

- Extract helper functions to src/cli/init-helpers.js (~750 lines)
- Extract generator functions to src/cli/init-generators.js (~400 lines)
- Reduce bin/musubi-init.js from 2404 to 1111 lines
- Update tests to use new module imports
- Exclude node_modules from complexity validation
- All Constitutional compliance checks pass (9/9 Articles)
- All 4827 tests passing

Author: hisaho

bin/musubi-init.js

@@ -1,6 +1,6 @@
 {
   "name": "musubi-sdd",
-  "version": "6.2.3",
+  "version": "6.2.0",
   "description": "Ultimate Specification Driven Development Tool with 27 Agents for 7 AI Coding Platforms + MCP Integration (Claude Code, GitHub Copilot, Cursor, Gemini CLI, Windsurf, Codex, Qwen Code)",
   "main": "src/index.js",
   "bin": {