electron-updater integration so users get fixes automatically:
- new dependency electron-updater@^6.6.2 in package.json
- electron-builder.config.js publishes to GitHub releases
(owner: concreteinfo, repo: markdownconverter)
- new src/main/auto-updater.js wraps autoUpdater: wires the six
lifecycle events to a 'updates:status' IPC channel, exposes
check() and install() helpers, dev-gates via isDev(), and
swallows the 'missing app-update.yml' error that dev runs hit
- main.js: ensureAutoUpdater() forwards status to the renderer
via mainWindow.webContents.send; ipcMain handlers for
'updates:check' (invoke) and 'updates:install' (invoke)
- preload.js: 'updates:check' / 'updates:install' added to
ALLOWED_SEND_CHANNELS; 'updates:status' added to receive
channels; electronAPI.updates.{check, install, onStatus}
exposed
7 new tests cover event registration, dev-gate behaviour,
'not-available' fallback for missing app-update.yml, typed event
payloads, error forwarding, and install() quitAndInstall.
Amit Haridas
