feat: ambient AI visit scribe (record/paste → reviewed SOAP note)

Record a clinician↔patient visit (or paste a transcript) on the patient
sheet; the backend transcribes it (OpenAI Whisper / Gemini), de-identifies
the transcript + context through Veil, and drafts a structured SOAP note
the clinician reviews and edits before saving — the same write-approval
gate as the chat agent.

Backend: POST /api/scribe/{transcribe,draft,save} (routes/scribe.ts,
services/ai/transcribe.ts), veil.redactText() free-text redactor,
appendEncounter service, audio MIME types on attachments. Gated by
patient:write + the clinic AI policy (reception/disabled-AI excluded).
Frontend: ScribeDialog + lib/scribe.ts, "Record visit" on the patient
detail, gated by clinical access + AI availability. New `scribe` locale
namespace across all five languages. Bumps to v0.4.0.

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

backend/src/services/patients.ts

@@ -570,6 +570,46 @@ export async function appendLabs(
   return getPatient(orgId, fileNumber);
 }
 
+// Append a single encounter (visit note) without touching the rest of the
+// record — used by the ambient AI scribe, which drafts one note at a time and
+// must not go through updatePatient's wholesale child replacement. Position
+// continues after the current max so the new note sorts last.
+export async function appendEncounter(
+  orgId: string,
+  fileNumber: string,
+  entry: Encounter,
+): Promise<Patient | null> {
+  const inserted = await db.transaction(async (tx) => {
+    const [existing] = await tx
+      .select({ id: patients.id })
+      .from(patients)
+      .where(
+        and(
+          eq(patients.organizationId, orgId),
+          eq(patients.fileNumber, fileNumber),
+        ),
+      );
+    if (!existing) return false;
+
+    const [pos] = await tx
+      .select({ max: sql<number>`coalesce(max(${encounters.position}), -1)` })
+      .from(encounters)
+      .where(eq(encounters.patientId, existing.id));
+    await tx.insert(encounters).values({
+      patientId: existing.id,
+      position: (pos?.max ?? -1) + 1,
+      ...entry,
+    });
+    await tx
+      .update(patients)
+      .set({ updatedAt: new Date() })
+      .where(eq(patients.id, existing.id));
+    return true;
+  });
+  if (!inserted) return null;
+  return getPatient(orgId, fileNumber);
+}
+
 // Remove a single lab result from a patient, identified by its
 // name/value/takenAt (the frontend has no row id). Scoped to the org via the
 // owning patient. Returns the reloaded patient, or null when the chart is gone.