feat: laundry-list polish pass

Seven bundled improvements:
- PartModel combobox on Add Part + Log Repair (known MPN auto-fills;
  unknown reveals manufacturer picker for catalog upsert).
- Host lifecycle: state (DEPLOYED/DEGRADED/TESTING) and stack
  (PRODUCTION/VETTING) fields, driven by external clients via the API.
- Locations page redesigned as a 2-pane tree + bin grid with breadcrumb.
- PENDING_REPAIR custody state: tech takes a SPARE into custody for a
  future swap; resolves to DEPLOYED via Repair or back to SPARE via a
  bin-required drop-off.
- Move Category from Part to PartModel; seed common categories
  (GPU/RAM/SSD/HDD/NIC/CPU/PSU/MOBO). Parts table gets a Category
  column and filter sourced from the model.
- Fix Deployed Value 100x bug on the Dashboard (price is stored as
  dollars, not cents).
- PartModels table shows "No" instead of "--" when destroyOnFail=false.

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

packages/db/prisma/seed.ts

@@ -17,6 +17,16 @@ async function main() {
 
   console.log(`Seeded admin user: ${admin.username} (${admin.email})`);
   console.log('Default password: admin — change this immediately!');
+
+  const categoryNames = ['GPU', 'RAM', 'SSD', 'HDD', 'NIC', 'CPU', 'PSU', 'MOBO'];
+  for (const name of categoryNames) {
+    await prisma.category.upsert({
+      where: { name },
+      update: {},
+      create: { name },
+    });
+  }
+  console.log(`Seeded ${categoryNames.length} part categories.`);
 }
 
 main()