feat: add AI recall calling — books existing patients for routine cleanings

Adds a new recall conversation flow (recall-graph.ts) triggered from the
Patient Connection "AI Call" button: offers an existing patient a routine
exam & cleaning, classifies their yes/no reply, then books directly onto
the schedule (Column A, 30-minute slots, real conflict checking against
office hours and existing appointments) instead of only capturing a
preference for staff to follow up on.

Also adds a "Voice call" label in the message thread to distinguish call
transcripts from SMS, and updates the Call Templates settings UI with an
editable recall greeting.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

apps/Backend/src/routes/twilio.ts

@@ -127,7 +127,7 @@ router.post("/make-ai-call", async (req: Request, res: Response): Promise<any> =
     const userId = req.user?.id;
     if (!userId) return res.status(401).json({ message: "Unauthorized" });
 
-    const { to, patientId } = req.body;
+    const { to, patientId, purpose } = req.body;
     if (!to || !patientId) return res.status(400).json({ message: "to and patientId are required" });
 
     const settings = await storage.getTwilioSettings(userId);
@@ -149,7 +149,8 @@ router.post("/make-ai-call", async (req: Request, res: Response): Promise<any> =
     } catch (err: any) {
       return res.status(500).json({ message: err.message });
     }
-    const webhookUrl = `${publicBaseUrl}/api/twilio/webhook/ai-voice?patientId=${patient.id}`;
+    const callPurpose = purpose === "recall" ? "recall" : "reminder";
+    const webhookUrl = `${publicBaseUrl}/api/twilio/webhook/ai-voice?patientId=${patient.id}&purpose=${callPurpose}`;
 
     const client = getTwilioClient(settings.accountSid, settings.authToken);
     const call = await client.calls.create({