Bundled plugins ship with source but not node_modules. When a bundled
plugin is enabled and has external dependencies, the loader now
automatically runs npm install on first load.
This fixes the issue where plugins like tlon (which depend on
@urbit/http-api and @urbit/aura) would fail to load from a fresh
npm install because their dependencies weren't installed.
Changes:
- loader.ts: Add ensureBundledPluginDeps() to install deps before loading
- docs/channels/tlon.md: Update to reflect bundled status and auto-install
- docs/plugin.md: Add tlon to plugin list, update dep install guidance
- docs/reference/RELEASING.md: Clarify bundled vs npm-published plugins
