feat: keyboard shortcuts for reveal mode and enable toggle

Alt+Shift+R — toggle reveal mode (fake→real in responses)
Alt+Shift+S — toggle Silent Send on/off

Badge flashes "EYE" (blue) when reveal activates, "ON"/"OFF"
(green/red) when toggling enabled state. Users can remap these
in chrome://extensions/shortcuts or Firefox about:addons.

https://claude.ai/code/session_01Dvgwe7XMoSxnWXkih8p1Cw

manifest.json

@@ -54,6 +54,22 @@
     "48": "icons/icon48.svg",
     "128": "icons/icon128.svg"
   },
+  "commands": {
+    "toggle-reveal": {
+      "suggested_key": {
+        "default": "Alt+Shift+R",
+        "mac": "Alt+Shift+R"
+      },
+      "description": "Toggle Reveal Mode"
+    },
+    "toggle-enabled": {
+      "suggested_key": {
+        "default": "Alt+Shift+S",
+        "mac": "Alt+Shift+S"
+      },
+      "description": "Toggle Silent Send on/off"
+    }
+  },
   "optional_host_permissions": [
     "https://*/*",
     "http://*/*"