v6.8.15: the Android app is out for testing

- Android APK download, served from securebit.chat (/downloads/, never
  committed): a "Download Android APK" badge next to the Snap Store one, drawn
  for both themes, and an Android entry in the download menu (recommended on
  Android devices). nginx serves .apk as an attachment; the service worker
  leaves /downloads/ alone. The APK version is one constant in three places,
  checked by tests/desktop-download-links.test.mjs.
- Roadmap versions follow the real releases: Group Communications v6.0
  shipped, Mobile Edition v6.8 is current, Quantum-Resistant v7.0 is in
  development (2027), then v8.0 and v9.0.
- "Download desktop app" is now "Download the app"; the "You're on Web" pill
  in the download menu is gone.

locales/en.json

@@ -223,7 +223,7 @@
     ],
     "roadmap.r9.title": "Group Communications",
     "roadmap.r9.sub": "Group chats with preserved privacy",
-    "roadmap.r9.date": "Now",
+    "roadmap.r9.date": "Fall 2026",
     "roadmap.r9.features": [
       "P2P group chats up to 8 participants",
       "Mesh delivery with signed relay fallback",
@@ -236,7 +236,7 @@
     ],
     "roadmap.r10.title": "Mobile Edition",
     "roadmap.r10.sub": "Native mobile apps for iOS and Android",
-    "roadmap.r10.date": "Q2 2027",
+    "roadmap.r10.date": "Now",
     "roadmap.r10.features": [
       "iOS native app (Swift/SwiftUI)",
       "Android native app (Kotlin/Jetpack Compose)",
@@ -249,7 +249,7 @@
     ],
     "roadmap.r11.title": "Quantum-Resistant Edition",
     "roadmap.r11.sub": "Protection against quantum computers",
-    "roadmap.r11.date": "Q4 2027",
+    "roadmap.r11.date": "2027",
     "roadmap.r11.features": [
       "Post-quantum cryptography CRYSTALS-Kyber",
       "SPHINCS+ digital signatures",
@@ -351,7 +351,7 @@
     "action.copy": "Copy",
     "action.copied": "Copied",
     "action.scan": "Scan",
-    "action.downloadDesktop": "Download desktop app",
+    "action.downloadDesktop": "Download the app",
     "action.advancedSettings": "Advanced settings",
     "cred.reveal": "Click to reveal - keep this code private",
     "cred.orCopy": "Or copy the code",
@@ -646,7 +646,7 @@
     "sec.simulatedWarning": "Warning: connection may not be fully established - values may be simulated.",
     "dl.title": "Download SecureBit",
     "dl.free": "Free · open source",
-    "dl.soon": "Mobile (iOS, Android) and browser extensions (Chrome, Firefox, Opera) are coming soon.",
+    "dl.soon": "The iOS app and browser extensions (Chrome, Firefox, Opera) are coming soon.",
     "chatHdr.chat": "Chat",
     "chatHdr.chats": "Chats",
     "chatHdr.newChat": "+ New",
@@ -795,7 +795,6 @@
     "offline.disconnect": "Disconnect",
     "offline.learnMore": "Learn more",
     "pwa.installApp": "Install App",
-    "chat.onWeb": "You're on Web",
     "groupCall.startVoice": "Start a group voice call",
     "groupCall.startVideo": "Start a group video call",
     "groupCall.join": "Join",