feat(wavelog): push station frequency/mode to Wavelog per operator

Add a CAT integration so the station's current frequency and mode are
reported to each operator's personal Wavelog logbook via Wavelog's radio
API (POST <baseUrl>/index.php/api/radio).

- New plugin rms.wavelog.cat (capability logging.cat.publish): posts
  {key, radio, frequency, mode}. Base URL / radio name come from plugin
  settings or env (WAVELOG_BASE_URL, WAVELOG_RADIO_NAME); no secrets in repo.
- Core hook in the OpenWebRX band-select flow pushes centerFreqHz + startMod
  for the active operator, best-effort (never breaks the band change).
- Per-user Wavelog API key stored on the user record; PUT /v1/me/wavelog-key
  to set it, returned by GET /v1/me and the OpenWebRX session issue response.
- UI: Wavelog API key field in the OpenWebRX panel (visible when generating
  the session link), with i18n (de/en).
- Docs, .env.example entries, and a unit test for the mode mapping.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

plugins/rms.wavelog.cat/manifest.json

@@ -0,0 +1,18 @@
+{
+  "id": "rms.wavelog.cat",
+  "name": "Wavelog CAT",
+  "version": "1.0.0",
+  "apiVersion": "1.0",
+  "capabilities": [
+    "logging.cat.publish"
+  ],
+  "settingsSchema": {
+    "type": "object",
+    "properties": {
+      "baseUrl": { "type": "string" },
+      "radioName": { "type": "string" },
+      "timeoutMs": { "type": "number", "minimum": 1000, "maximum": 60000 }
+    },
+    "additionalProperties": false
+  }
+}