feat(notifications): requests and flags reach the people who act on them (#5340)

- A new request still pending after any auto-approval notifies the
  admins (request_pending), but not the requester if they are an admin.
  A request that dedups into one already in flight is not announced again.
- Approving or rejecting a request notifies the requester, and a
  rejection carries the admin's notes as the reason. An admin deciding
  their own request gets nothing.
- The reconciler notifies the requester when their request arrives
  (request_completed), linking the matched album or artist.
- A request the re-acquisition sweeper files and cannot approve itself
  notifies the admins.
- A quarantine flag notifies every admin except the flagger, naming the
  track, the flagger and the reason.

lidarrrequests.Service.CreateTracked reports whether a request was
inserted or deduped; Create wraps it.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/api/quarantine.go

@@ -9,6 +9,7 @@ import (
 	"git.fabledsword.com/bvandeusen/minstrel/internal/apierror"
 	"git.fabledsword.com/bvandeusen/minstrel/internal/db/dbq"
 	"git.fabledsword.com/bvandeusen/minstrel/internal/lidarrquarantine"
+	"git.fabledsword.com/bvandeusen/minstrel/internal/notifications"
 )
 
 // quarantineView is the JSON shape returned by the user-facing endpoints
@@ -70,6 +71,10 @@ func (h *handlers) handleFlag(w http.ResponseWriter, r *http.Request) {
 	// Broadcast: the flagging user's other clients invalidate their
 	// Hidden tab; admins' clients invalidate their quarantine queue.
 	h.publishQuarantineEvent("quarantine.flagged", user.ID, trackID, true)
+	// Admins review flags (M489). An admin flagging a track needs no notice
+	// of their own flag.
+	h.notifier.NotifyLogged(r.Context(), notifications.KindQuarantineFlagged, notifications.ToAdmins(user.ID),
+		notifications.Payload{Name: h.trackLabel(r.Context(), trackID), Actor: userLabel(user), Reason: quarantineReasonLabel(body.Reason)}.Map())
 	writeJSON(w, http.StatusCreated, quarantineViewFrom(row))
 }