collector: RSSI of connected sensors via kernel mgmt API

BlueZ fills Device1.RSSI only while scanning; sensors connect to us, so
the field stayed empty. MGMT_OP_GET_CONN_INFO (like btmgmt conn-info)
returns the link RSSI; polled per connected sensor and after each write.
Needs CAP_NET_ADMIN (AmbientCapabilities in the collector unit).

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

collector/bluez_adv.py

@@ -1,5 +1,5 @@
 #!/usr/bin/env python3
-"""BlueZ helpers for connected devices (RSSI / disconnect). Advertising is via bless.
+"""BlueZ helpers for connected devices (list / disconnect). Advertising is via bless.
 
 All calls here are blocking (python3-dbus). main.py runs them in a worker
 thread with a timeout, so they must raise on failure instead of returning
@@ -8,7 +8,8 @@ empty results: an empty list would look like "everyone disconnected".
 from __future__ import annotations
 
 import logging
-from typing import Dict, Optional
+import re
+from typing import Dict, Optional, Tuple
 
 log = logging.getLogger("collector.bluez_adv")
 
@@ -54,16 +55,21 @@ def bluez_owner(bus) -> Optional[str]:
         raise
 
 
-def connected_devices(bus) -> Dict[str, Optional[int]]:
-    """{ADDR: rssi or None} for all connected devices. Raises on D-Bus errors."""
-    out: Dict[str, Optional[int]] = {}
+def connected_devices(bus) -> Dict[str, Tuple[str, int]]:
+    """{ADDR: (address type, controller index)} for all connected devices.
+
+    Device1.RSSI is not used: BlueZ sets it only while scanning, and sensors
+    connect to us. RSSI comes from mgmt.conn_rssi(), which needs these two.
+    Raises on D-Bus errors."""
+    out: Dict[str, Tuple[str, int]] = {}
     for _path, ifaces in _managed_objects(bus).items():
         dev = ifaces.get(DEVICE_IFACE)
         if not dev or not bool(dev.get("Connected", False)):
             continue
         addr = str(dev.get("Address", "")).upper()
-        rssi = dev.get("RSSI")
-        out[addr] = int(rssi) if rssi is not None else None
+        addr_type = str(dev.get("AddressType", "random"))
+        m = re.search(r"/hci(\d+)$", str(dev.get("Adapter", "")))
+        out[addr] = (addr_type, int(m.group(1)) if m else 0)
     return out