feat: deploy ask TUI to ask.xn--2dk.xyz

- Add ttyd service for ask on port 7682
- Update haloy.yml with new domain and GEMINI_API_KEY
- Update Caddyfile to route ask.xn--2dk.xyz to ttyd
- Update Dockerfile to include ask binary
- Update README with ask section and schema files documentation

Caddyfile

@@ -3,6 +3,27 @@
         respond 200
     }
 
+    # ask.xn--2dk.xyz - Natural language to SQL TUI
+    ask.xn--2dk.xyz {
+        @websocket {
+            header Connection *Upgrade*
+            header Upgrade websocket
+        }
+
+        handle @websocket {
+            reverse_proxy localhost:7682 {
+                flush_interval -1
+            }
+        }
+
+        handle {
+            reverse_proxy localhost:7682 {
+                flush_interval -1
+            }
+        }
+    }
+
+    # db.xn--2dk.xyz - DuckDB SQL shell
     handle /login {
         reverse_proxy 127.0.0.1:8081
     }