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>

public/index.html

@@ -166,6 +166,15 @@
               <div id="openwebrxSessionAccess" class="stack" hidden>
                 <p class="muted">Session Key (Ticket): <code id="openwebrxSessionTicket">-</code></p>
               </div>
+              <div id="wavelogKeyBox" class="stack">
+                <label for="wavelogKeyInput">Wavelog API Key (Rig-Key)</label>
+                <input id="wavelogKeyInput" type="text" autocomplete="off" spellcheck="false" placeholder="Wavelog API Key" />
+                <div class="actions">
+                  <button id="wavelogKeySaveBtn" type="button" class="ghost-btn">Key speichern</button>
+                </div>
+                <p id="wavelogKeyMessage" class="message"></p>
+                <p class="muted">Frequenz und Mode der Station werden beim Bandwechsel an dein Wavelog-Logbuch gesendet.</p>
+              </div>
             </section>
 
             <section id="reservationPanel" class="links-wrap" hidden>