fix: prevent silent muting from hiding pager messages

The "Mute" button on pager cards persists muted addresses to
localStorage with no visible indicator, making it easy to
accidentally hide an address and forget about it. This caused
flag fragment messages on RIC 1337 to silently disappear.

- Add "X muted source(s) — Unmute All" indicator to sidebar
- Stop persisting hideToneOnly filter across sessions so the
  default (show all) always applies on page load
- Remove default checked state from Tone Only filter checkbox

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

templates/partials/modes/pager.html

@@ -62,7 +62,7 @@
         <h3>Message Filters</h3>
         <div class="checkbox-group" style="margin-bottom: 10px;">
             <label>
-                <input type="checkbox" id="filterToneOnly" checked onchange="savePagerFilters()">
+                <input type="checkbox" id="filterToneOnly" onchange="savePagerFilters()">
                 Hide "Tone Only" messages
             </label>
         </div>
@@ -73,6 +73,14 @@
         <div class="info-text" style="font-size: 10px; color: #666; margin-top: 5px;">
             Messages matching these keywords will be hidden from display but still logged.
         </div>
+        <div id="mutedAddressInfo" style="margin-top: 8px; display: none;">
+            <span style="font-size: 11px; color: var(--text-dim, #888);">
+                <span id="mutedAddressCount">0</span> muted source(s)
+            </span>
+            <button onclick="SignalCards.unmuteAll()" style="margin-left: 6px; font-size: 10px; padding: 2px 8px; cursor: pointer; background: transparent; border: 1px solid var(--border-color, #444); color: var(--text-secondary, #aaa); border-radius: 3px;">
+                Unmute All
+            </button>
+        </div>
     </div>
 
     <!-- Antenna Guide -->