feat: split Repairs into FM, Repair, and Custody workflows

The old Repairs module had grown ticketing-system features (status lifecycle,
comments, assignee, notes) that duplicate what the external ticketing tool
already owns. Vector only needs to track whether maintenance is open or closed.

- Rename RepairJob -> Fm (OPEN/CLOSED only), drop RepairComment, assignee, notes
- New Repair table: persistent log of physical part swaps, with ingest on
  unknown broken MPN via partModels.upsertByMpn
- New custody model: PENDING_DROP_IN_CUSTODY / PENDING_DESTRUCTION_IN_CUSTODY
  states + Part.custodianId, with a "My Custody" page for drop-off
- PartModel.destroyOnFail routes broken parts to the destruction path
- Host lookup on /fms and /repairs accepts hostId XOR assetId
- Wire the dormant webhook emitter: fm.opened, fm.closed, repair.logged
- Single fresh Prisma migration (dev DB was wiped, no backfill)

Tests: 60 passing (custody transitions in parts.test.ts; new fms.test.ts,
repairs.test.ts, custody.test.ts covering happy paths, validation failures,
webhook emissions, and ingest-on-unknown-MPN).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

apps/web/src/pages/Parts.tsx

@@ -116,7 +116,7 @@ export default function Parts() {
         id: 'location',
         header: 'Location',
         cell: ({ row }) => {
-          const host = row.original.host;
+          const { host, custodian, bin } = row.original;
           if (host) {
             return (
               <span className="text-xs font-mono text-muted-foreground">
@@ -124,9 +124,15 @@ export default function Parts() {
               </span>
             );
           }
-          const path = row.original.bin?.fullPath;
-          return path ? (
-            <span className="text-xs font-mono text-muted-foreground">{path}</span>
+          if (custodian) {
+            return (
+              <span className="text-xs text-muted-foreground">
+                Custody: {custodian.username}
+              </span>
+            );
+          }
+          return bin?.fullPath ? (
+            <span className="text-xs font-mono text-muted-foreground">{bin.fullPath}</span>
           ) : (
             <span className="text-xs text-muted-foreground italic">Unassigned</span>
           );