chore: bump version to v0.30.1

Update version across all packages:
- Go CLI (cmd/bd/version.go)
- Python MCP server (pyproject.toml, __init__.py)
- npm package (package.json)

Add comprehensive CHANGELOG entry with 14 features, 14 fixes,
security updates, and community contributor credits.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

npm-package/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@beads/bd",
-  "version": "0.30.0",
+  "version": "0.30.1",
   "description": "Beads issue tracker - lightweight memory system for coding agents with native binary support",
   "main": "bin/bd.js",
   "bin": {