feat: ChannelScanEntryDict + get_channel_scan / push_radio_channel interface

Adds ChannelScanEntryDict TypedDict for iw-scan results (bssid, ssid,
frequency, channel, signal_dbm, channel_width, band).

AccessPointDriver gains two new interface methods:
- get_channel_scan(mode) → dict[iface, list[ChannelScanEntryDict]]
  Default returns {} so non-implementing drivers degrade gracefully.
- push_radio_channel(radio, channel) — abstract (raises NotImplementedError).

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

napalm_device_types/access_point.py

@@ -14,6 +14,7 @@ from typing import Any, Dict, List
 from napalm_device_types.base import DeviceTypeDriver
 from napalm_device_types._ucd_metrics import IF_SKIP_DEFAULT, collect_ucd_metrics
 from napalm_device_types.models import (
+    ChannelScanEntryDict,
     Dot1XConfigDict,
     FastTransitionConfigDict,
     HealthMetricsDict,

napalm_device_types/models.py

@@ -105,6 +105,18 @@ class RadioStatusDict(TypedDict):
     frequency: float
 
 
+class ChannelScanEntryDict(TypedDict):
+    """One neighboring AP entry as returned by get_channel_scan()."""
+
+    bssid: str
+    ssid: str
+    frequency: int      # centre frequency in MHz, e.g. 2437
+    channel: int        # channel number, e.g. 6
+    signal_dbm: int     # RSSI in dBm, e.g. -72
+    channel_width: int  # MHz: 20 / 40 / 80 / 160; 0 if unknown
+    band: str           # "2.4GHz" | "5GHz" | "6GHz"
+
+
 class WirelessConfigDict(TypedDict):
     country_code: str
     regulatory_domain: str