feat(mpris): pin preferred media source

[scottsteely]

Description

Add a minimal "pin media source" option so the bar media widget and OSD keep showing a preferred player (e.g. a music player) even when another source (e.g. YouTube in the browser) starts playing.

• MprisController: new pinnedIdentity property + setPinned(identity); _bestPlayingPlayer() prefers a playing pinned player (exact identity match, then case-insensitive substring fallback). Existing behavior is unchanged when no pin is set.
• Persistence via SessionData.pinnedPlayerIdentity (spec entry added so SessionData.set() accepts the key); empty string clears the pin.
• MediaDropdownOverlay (Media Players panel): each player row gets a theme-colored circle indicator on the right. Empty circle = no pin (initial state). Right-click a row to make it the default source (circle fills); right-click another row to move the pin; right-click the pinned row again to clear (back to empty). Left-click behavior unchanged (selects the player).

Type of change

• Bug fix (non-breaking change that fixes an issue)
• [ X] New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that changes existing behavior)
• Refactor / internal cleanup
• Documentation
• Other

Related issues

Screenshots / video

Checklist

• [X ] My code follows the conventions in CONTRIBUTING.md
• [X ] I have tested my changes locally
• [X ] New user-facing strings are wrapped in I18n.tr() with translator context, reusing existing terms where possible
• [ X] Go changes: ran make fmt, added/updated tests, make test passes, and go mod tidy is clean
• [X ] QML changes: ran make lint-qml with no new warnings
• I have opened a corresponding pull request in dlx-docs to document any new behaviors: https://github.com/AvengeMedia/DankLinux-Docs
  i'll do that last one next

[hthienloc]

/claude review

[claude]

Claude review

One minor issue; the feature itself looks sound and existing selection behavior is preserved when no pin is set.

• setPinned() imperatively assigns pinnedIdentity, destroying its binding to SessionData.pinnedPlayerIdentity (redundant, since SessionData.set() already propagates) — quickshell/Services/MprisController.qml:313

Checked: pin resolution order in _bestPlayingPlayer(), SessionData spec/persistence round-trip, delegate layout and right-click handling in MediaDropdownOverlay (no new user-facing strings, en.json/template.json untouched, no Go changes). Model: claude-opus-5.

[bbedward]

/claude review

[claude]

The pin branch returns before every canControl check the rest of this function is built around, so a pinned player that is playing but not controllable becomes activePlayer and the transport controls go dead — the existing code deliberately swaps to a same-track controllable mirror in that case (line 263).

This is reachable because identity is not unique: browsers register one MPRIS service per tab under the same identity ("Chromium", "Mozilla Firefox"), and find takes whichever comes first, which may be the uncontrollable instance.

Prefer a controllable match before falling back:

Suggested change

	if (pinnedIdentity !== "") {
	const pinLower = pinnedIdentity.toLowerCase();
	const pinned = playing.find(player => player.identity === pinnedIdentity) ?? playing.find(player => (player.identity || "").toLowerCase().includes(pinLower));
	if (pinned)
	return pinned;
	}
	if (pinnedIdentity !== "") {
	const pinLower = pinnedIdentity.toLowerCase();
	const exact = playing.filter(player => player.identity === pinnedIdentity);
	const matches = exact.length > 0 ? exact : playing.filter(player => (player.identity || "").toLowerCase().includes(pinLower));
	const pinned = matches.find(player => player.canControl) ?? matches[0];
	if (pinned)
	return pinned;
	}

[claude]

Claude review

One finding; the previously-flagged binding-destroying assignment in setPinned() is fixed, and the rest looks sound.

• Pin resolution bypasses the canControl handling the rest of _bestPlayingPlayer() relies on, so a pinned-but-uncontrollable player (identities are not unique — one MPRIS service per browser tab) can take over and kill the transport controls — quickshell/Services/MprisController.qml:251

Checked: pin resolution order and interaction with the existing mirror/paused paths, SessionData spec + persistence round-trip (empty string clears, toJson drops defaults), delegate layout and right-click handling in MediaDropdownOverlay (imports, id scoping, no binding loop). No new user-facing strings; en.json/template.json untouched; no Go changes. Model: claude-opus-5.