[codex] Prepare registry metadata and safer install prompts

[nanami-he]

Summary

• Sync local maintenance branch from merged main and continue the PRD 1/2/4/5 workstream.
• Add MCP Registry metadata with server.json, package.json#mcpName, and a registry publishing checklist.
• Make the installer show the existing config and ask before replacing a non-petsonality statusLine or stale petsonality/typet hook entries.
• Improve GitHub issue templates by fixing the statusline smoke command and adding more useful feature-request fields.
• Update PRD progress for G0 registry metadata, M4 install transparency, and M6 templates.

Validation

• bun test -> 322 pass, 0 fail
• bun run build -> succeeds; generated dist/cli/install.js updated
• NPM_CONFIG_CACHE=/private/tmp/petsonality-npm-cache npm pack --dry-run -> succeeds; tarball contains expected 15 files including dist/cli/install.js, dist/server.js, and package.json
• node -e "JSON.parse(...)" over server.json and package.json -> json ok

Registry note

This prepares registry metadata but does not publish Petsonality to the MCP Registry yet. The currently published npm petsonality@0.4.5 predates package.json#mcpName, so the actual mcp-publisher publish step should wait until the next npm version is published with that field included.