ha: add carefree_bt12 integration for the Carefree Connects awning

Commands reverse-engineered from Bluetooth HCI snoop captures (adb bugreport)
of the official Carefree Connects (BT12) Android app, confirmed across three
independent captures including two isolated single-action live tests:
extend/retract (feature 0x05, values 0x01/0x02 -- the device toggles motor
state internally, there's no separate stop byte) and light on/off (feature
0x1a, values 0x19/0x01). Both live under GATT characteristic 02060002 on
service 02060001-50e1-405f-bab0-6bb582b4d96e.

Connects on demand per command (mirrors the app's own connect/act/disconnect
pattern) rather than holding a persistent connection like li3_battery, since
this device doesn't stream telemetry. Cover/light state is assumed/optimistic
-- the notify channel (02060003) isn't decoded yet, so a diagnostic sensor
just surfaces raw undecoded replies to build up data for that follow-on work.

Verified end-to-end against the real device: light on/off and awning
extend both worked through Home Assistant.

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

ha/custom_components/carefree_bt12/manifest.json

@@ -0,0 +1,17 @@
+{
+  "domain": "carefree_bt12",
+  "name": "Carefree Connects BT12 Awning",
+  "codeowners": ["@aew"],
+  "config_flow": true,
+  "dependencies": ["bluetooth"],
+  "documentation": "https://github.com/wrede/vanlink",
+  "iot_class": "local_push",
+  "requirements": ["bleak-retry-connector>=3.0.0"],
+  "version": "0.1.0",
+  "bluetooth": [
+    {
+      "local_name": "BT12",
+      "connectable": true
+    }
+  ]
+}