feat: add internal AI chat assistant and AI Input Agent page

- Add Gemini-powered internal staff chatbot (free-text input in the
  upper-right bot panel): type "check MARIA GONZALES" to search patient
  and pre-fill eligibility, or "open claims" to navigate directly
- Add /api/ai/internal-chat endpoint with LangGraph + Google Gemini
  classifier (intent: check_eligibility, find_patient, navigate_*)
- Add Users AI Chat settings section in Settings > Advanced > AI Chat
  to configure a custom system prompt for the internal assistant
- Store internal chat system prompt in existing twilioSettings JSON
  blob (no DB migration needed)
- Add AI Input Agent sidebar entry and placeholder page describing
  planned keyboard-automation typing into Open Dental / Eaglesoft

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/Frontend/src/pages/ai-input-agent-page.tsx

@@ -0,0 +1,137 @@
+import { Bot, Keyboard, FileCheck, CreditCard, Shield, Zap, ArrowRight } from "lucide-react";
+import { Card, CardContent } from "@/components/ui/card";
+
+const SOFTWARE_TARGETS = [
+  { name: "Open Dental", color: "bg-blue-100 text-blue-700 border-blue-200" },
+  { name: "Eaglesoft", color: "bg-emerald-100 text-emerald-700 border-emerald-200" },
+  { name: "Dentrix", color: "bg-violet-100 text-violet-700 border-violet-200" },
+  { name: "Curve Dental", color: "bg-orange-100 text-orange-700 border-orange-200" },
+];
+
+const CAPABILITIES = [
+  {
+    icon: <Shield className="h-5 w-5 text-teal-600" />,
+    title: "Eligibility Results",
+    description:
+      "Automatically type insurance eligibility information — coverage status, plan details, deductibles, and co-pays — directly into the patient chart in your dental software.",
+  },
+  {
+    icon: <FileCheck className="h-5 w-5 text-blue-600" />,
+    title: "Claim Information",
+    description:
+      "Transfer claim numbers, claim status updates, and denial reasons from the insurance portal results into your claims module without manual re-entry.",
+  },
+  {
+    icon: <CreditCard className="h-5 w-5 text-indigo-600" />,
+    title: "Insurance Payments",
+    description:
+      "Post ERA / EOB payment details — amounts, adjustments, patient responsibility — directly into your payment ledger by typing them into the active software window.",
+  },
+];
+
+export default function AiInputAgentPage() {
+  return (
+    <div className="max-w-3xl mx-auto px-4 py-10 space-y-10">
+
+      {/* Hero */}
+      <div className="text-center space-y-3">
+        <div className="inline-flex items-center justify-center w-16 h-16 rounded-2xl bg-violet-100 mb-2">
+          <Bot className="h-8 w-8 text-violet-600" />
+        </div>
+        <h1 className="text-3xl font-bold tracking-tight">AI Input Agent</h1>
+        <p className="text-muted-foreground text-base max-w-xl mx-auto">
+          An AI-powered agent that reads data from this app and types it directly into your
+          current dental management software — no copy-paste, no manual re-entry.
+        </p>
+        <span className="inline-block bg-amber-100 text-amber-700 text-xs font-semibold px-3 py-1 rounded-full border border-amber-200">
+          Coming Soon
+        </span>
+      </div>
+
+      {/* How it works */}
+      <Card>
+        <CardContent className="py-6 space-y-4">
+          <div className="flex items-center gap-2">
+            <Keyboard className="h-5 w-5 text-violet-500" />
+            <h2 className="text-base font-semibold">How it works</h2>
+          </div>
+          <div className="flex flex-col sm:flex-row items-start sm:items-center gap-3 text-sm">
+            {[
+              "Retrieve data in this app\n(eligibility, claim, payment)",
+              "Agent identifies the active\nfield in your dental software",
+              "Types the value directly\nvia keyboard automation",
+            ].map((step, i) => (
+              <div key={i} className="flex items-center gap-3 flex-1">
+                <div className="flex-shrink-0 w-7 h-7 rounded-full bg-violet-100 text-violet-700 text-xs font-bold flex items-center justify-center">
+                  {i + 1}
+                </div>
+                <p className="whitespace-pre-line text-muted-foreground leading-snug">{step}</p>
+                {i < 2 && <ArrowRight className="h-4 w-4 text-muted-foreground/40 hidden sm:block flex-shrink-0" />}
+              </div>
+            ))}
+          </div>
+          <p className="text-xs text-muted-foreground pt-1 border-t">
+            The agent runs as a lightweight local process on your workstation. It receives
+            instructions from this app and uses keyboard automation to type data into whatever
+            window is currently focused in your dental software — no clipboard involved.
+          </p>
+        </CardContent>
+      </Card>
+
+      {/* What it will type */}
+      <div className="space-y-3">
+        <h2 className="text-base font-semibold">What it will type</h2>
+        <div className="grid gap-4 sm:grid-cols-3">
+          {CAPABILITIES.map((cap) => (
+            <Card key={cap.title}>
+              <CardContent className="py-5 space-y-2">
+                <div className="flex items-center gap-2">
+                  {cap.icon}
+                  <span className="text-sm font-medium">{cap.title}</span>
+                </div>
+                <p className="text-xs text-muted-foreground leading-relaxed">
+                  {cap.description}
+                </p>
+              </CardContent>
+            </Card>
+          ))}
+        </div>
+      </div>
+
+      {/* Supported software */}
+      <div className="space-y-3">
+        <h2 className="text-base font-semibold">Planned software support</h2>
+        <div className="flex flex-wrap gap-2">
+          {SOFTWARE_TARGETS.map((s) => (
+            <span
+              key={s.name}
+              className={`text-sm font-medium px-3 py-1.5 rounded-lg border ${s.color}`}
+            >
+              {s.name}
+            </span>
+          ))}
+        </div>
+        <p className="text-xs text-muted-foreground">
+          Each software has its own field layout. The agent will include pre-built templates
+          for common workflows in each platform.
+        </p>
+      </div>
+
+      {/* Why */}
+      <Card className="border-violet-200 bg-violet-50/50">
+        <CardContent className="py-5 flex items-start gap-3">
+          <Zap className="h-5 w-5 text-violet-500 mt-0.5 flex-shrink-0" />
+          <div className="space-y-1">
+            <p className="text-sm font-medium text-violet-900">Why this matters</p>
+            <p className="text-sm text-violet-700 leading-relaxed">
+              Staff currently check eligibility or look up a claim here, then manually retype
+              every value into Open Dental or Eaglesoft. This agent eliminates that step entirely —
+              one click sends the data straight into the right field.
+            </p>
+          </div>
+        </CardContent>
+      </Card>
+
+    </div>
+  );
+}