feat: AI-added records save with placeholders + "Added by AI" provenance

Stop blocking AI imports/proposals on missing non-critical fields. Records
the chat agent drafts now save with safe placeholders, auto-generated file
numbers, and a source="ai" marker that surfaces an "Added by AI" badge so a
clinician can review/edit them later.

Backend:
- add `source` (manual|ai) column to patients/appointments/prescriptions
  (migration 0014) + canonical types, services, validation schemas
- relax patient/appointment validation: empty file number allowed, demographic
  + type/provider/initials fall back to placeholders (initials derived from name)
- patients.generateFileNumber() auto-assigns an MRN when one is missing
- proposeAppointment accepts a name when no file number resolves; AI commits +
  /api/ai/import stamp source="ai"

Frontend:
- `source` on Appointment/Patient/Prescription types; AI commits send source="ai"
- reusable <AiBadge> shown on the Patients table/detail and prescriptions list

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.agents/skills/ai-elements/scripts/file-tree-basic.tsx

@@ -0,0 +1,18 @@
+"use client";
+
+import {
+  FileTree,
+  FileTreeFile,
+  FileTreeFolder,
+} from "@/components/ai-elements/file-tree";
+
+const Example = () => (
+  <FileTree>
+    <FileTreeFolder name="src" path="src">
+      <FileTreeFile name="index.ts" path="src/index.ts" />
+    </FileTreeFolder>
+    <FileTreeFile name="package.json" path="package.json" />
+  </FileTree>
+);
+
+export default Example;