feat: complete remaining features — training, FTS, bot groups, repair, re-tag

Manual override training (GroupingRule):
- Learn patterns from manual group creation (common filename prefix or creator)
- Apply learned rules as first auto-grouping pass (highest confidence after albums)
- GroupingRule model stores pattern, channel, signal type, confidence

Hash verification after upload:
- Re-hash upload files on disk before indexing to catch disk corruption
- Creates HASH_MISMATCH notification on discrepancy

Grouping conflict detection:
- After all grouping passes, check if grouped packages match rules from different groups
- Creates GROUPING_CONFLICT notification for manual review

Per-channel grouping flags:
- Add autoGroupEnabled boolean to TelegramChannel (default true)
- Auto-grouping passes (all except album) gated behind this flag
- Album grouping always runs as it reflects Telegram's native behavior

Full-text search (tsvector):
- Add searchVector tsvector column with GIN index and auto-update trigger
- Backfill 1870 existing packages
- FTS with ts_rank for ranked results, ILIKE fallback for short/failed queries
- Applied to both web app and bot search

Bot group awareness:
- /group <query> — view group info or search groups by name
- /sendgroup <id> — send all packages in a group to linked Telegram account

Bulk repair:
- repairPackageAction clears dest info and resets watermark for re-processing
- Repair button in notification bell for MISSING_PART and HASH_MISMATCH alerts
- /api/notifications/repair endpoint

Retroactive category re-tagging:
- When channel category changes, auto-update tags on all existing packages
- Removes old category tag, adds new one

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/app/api/notifications/repair/route.ts

@@ -0,0 +1,43 @@
+import { NextResponse } from "next/server";
+import { auth } from "@/lib/auth";
+import { prisma } from "@/lib/prisma";
+
+export const dynamic = "force-dynamic";
+
+export async function POST(request: Request) {
+  const session = await auth();
+  if (!session?.user?.id) {
+    return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
+  }
+
+  const body = await request.json().catch(() => ({}));
+  const notificationId = body.notificationId as string;
+  if (!notificationId) {
+    return NextResponse.json({ error: "notificationId required" }, { status: 400 });
+  }
+
+  const notification = await prisma.systemNotification.findUnique({
+    where: { id: notificationId },
+  });
+
+  if (!notification) {
+    return NextResponse.json({ error: "Notification not found" }, { status: 404 });
+  }
+
+  const context = notification.context as Record<string, unknown> | null;
+  const packageId = context?.packageId as string | undefined;
+
+  if (!packageId) {
+    return NextResponse.json({ error: "Notification has no associated package" }, { status: 400 });
+  }
+
+  // Import and call the repair action
+  const { repairPackageAction } = await import("@/app/(app)/stls/actions");
+  const result = await repairPackageAction(packageId);
+
+  if (!result.success) {
+    return NextResponse.json({ error: result.error }, { status: 500 });
+  }
+
+  return NextResponse.json({ success: true });
+}