[Feature]: OS-level notification when a turn completes, so users in other apps know Claudian finished

Problem or unmet use case

When Claudian is working on a longer task, I typically switch to another app and do something else. When the turn finishes, there is no OS-level notification — nothing outside the Obsidian window tells me the response is ready, so I keep checking back manually.

As far as I can tell from the bundled main.js in v2.2.4, there is no system-notification call (no new Notification(...) / osascript-based notifications), and the README feature list doesn't mention completion notifications. In-app toasts (if any) don't help when Obsidian is not the focused app.

Desired outcome

An optional OS notification (macOS Notification Center / Windows toast / Linux libnotify) fired when a turn completes — ideally only when the Obsidian window is not focused, so foreground use stays quiet.

Affected provider

Not provider-specific (observed with Claude)

Proposed solution

A settings toggle like "System notification on completion". On macOS the Electron/HTML5 Notification API is enough (Obsidian needs to be allowed in System Settings → Notifications). Firing only when document.hasFocus() is false would avoid noise.

Alternatives considered

A Claude Code Stop hook (e.g. running osascript -e 'display notification ...' from ~/.claude/settings.json) works today, but it is a CLI-level workaround: it also fires in plain terminal sessions, needs manual setup, and is undiscoverable. Native support in Claudian would be cleaner and available to users of every provider.

Additional context

Claudian v2.2.4, macOS. Thanks for the plugin — it fits the vault workflow really well.