Refactor the journal server to run over WebSockets on the existing
HTTP server instead of a separate MQTT TCP port. This removes the need
for a separate port configuration and simplifies the connection flow
by auto-connecting to the current host.
- Remove `--mqtt-port` CLI option
- Attach Aedes broker to the HTTP server via WebSocket upgrade
- Update UI to remove manual broker URL and player name inputs
- Add "Content Source" access from the sidebar
- Update JournalPanel to auto-connect to the local server
Introduce a dialog for switching between built-in content and a
user-selected local folder. Persist the folder handle in IndexedDB
so the selection survives page refreshes. Scan the folder for .md,
.yarn, and .csv files to build the file index.
Update App and Sidebar to pass file tree and heading data, and
add TypeScript declarations for the File System Access API.