Merge origin/dev into feat/rag-clinical-guidelines

Conflict in app/api/routes.py: /demo/personas keeps the dev version (demo console, DB patients
with scenarios); the patient app gets its own /patient/demo-personas (synthetic ЕМИАС accounts).
Anonymous sign-in now always creates a doctor-less pseudonymous profile, since the dialog API
of #12 serves known profiles only.

Refs #77

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

app/dialog/flows/core.py

@@ -39,6 +39,7 @@ def menu_reply(ctx: Ctx, text: str | None = None) -> Reply:
     buttons = [
         [Button(label=b.checkin, data="menu:checkin")],
         [Button(label=b.med_question, data="menu:med_question")],
+        [Button(label=b.kb_question, data="menu:kb_question")],
         [Button(label=b.contact_doctor, data="menu:contact_doctor")],
         [Button(label=b.revoke, data="consent:revoke")],
     ]