fix(documents): encrypt staged extracted-fact PHI at rest

The inbound-document store encrypts the raw upload
(`inbound_documents.content_encrypted`) because it is sensitive clinical
data, but the per-fact staging columns persisted the same class of data in
the clear: `extracted_facts.data_json` held the transcribed clinical values
(diagnosis text, lab values, medication names, stated codes) and
`provenance_json` held the verbatim source span (up to 2000 chars copied
straight out of the report). The at-rest guarantee was defeated for staged
facts, which persist through PENDING and are retained after the decision.

Convert both columns to the AES-256-GCM `*_encrypted` BYTEA convention shared
with the note columns, going through the same Bytes codec. The upload and
fact-edit paths encrypt on write; the confirm path decrypts at commit time to
write into the normal structured stores, so the review-then-confirm flow is
unchanged. Reads are fail-closed (a bad key id throws).

Register both columns in the encrypted-columns registry and the key-rotation
script so a dropped legacy key cannot strand them (the guard test enforces
both). Migration 0220 swaps the plaintext JSONB columns for the encrypted
BYTEA columns; pre-confirm staged rows are ephemeral and cannot be
re-encrypted in SQL, so any left by a pre-release build are dropped rather
than retained as plaintext (their parent document keeps its encrypted
original).

scripts/rotate-encryption-key.ts

@@ -486,6 +486,22 @@ async function main() {
       prisma.inboundDocument,
     ),
   );
+  // The staged extracted-fact payloads: the FHIR-staged clinical values and the
+  // verbatim source-span provenance. Both NOT NULL, so every staged row rotates.
+  results.push(
+    await rotateBytesColumn(
+      "ExtractedFact",
+      "dataEncrypted",
+      prisma.extractedFact,
+    ),
+  );
+  results.push(
+    await rotateBytesColumn(
+      "ExtractedFact",
+      "provenanceEncrypted",
+      prisma.extractedFact,
+    ),
+  );
 
   console.log("\n=== Rotation summary ===");
   let totalRotated = 0;