Android overhaul: stale comments and the module README

* Milestone and ownership notes that no longer hold ("owned by M5/M6/M8", "M8 replaces it", "(M8b)", "M7x add",
  "proposed decision in the M5 report", which is D-027 and D-028) in build scripts, :core:design, :core:fakes, :data,
  :app, :core:model and the settings string files.
* SyncEngine: the clock_skew KDoc sat orphaned above restampAfterClockSkew's; it now documents renewMutationId.
* libs.versions.toml header: no milestone, the drift date.
* README: the module table as built (no owners, no DebugFakesModule, which M8 removed), the test fixtures in the
  architecture check and the shared screenshot harness.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TQd3pEP9UeN2uifbHknQ7B

android/app/src/main/kotlin/se/hagstedt/kvitt/KvittEmptyScreen.kt

@@ -10,7 +10,7 @@ import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.res.stringResource
 
-/** The M2b shell: the themed surface with the app name. M8 replaces it with the navigation graph. */
+/** The themed surface with the app name, shown until the session state has loaded (KvittApp). */
 @Composable
 fun KvittEmptyScreen(modifier: Modifier = Modifier) {
     Surface(modifier = modifier.fillMaxSize(), color = MaterialTheme.colorScheme.background) {

android/app/src/main/kotlin/se/hagstedt/kvitt/MainActivity.kt

@@ -28,7 +28,7 @@ class MainActivity : ComponentActivity() {
         super.onCreate(savedInstanceState)
         enableEdgeToEdge()
         if (savedInstanceState == null) app.onLink(AppLinks.parse(intent))
-        // `:core:design` reads "now" and the zone from :data's clock (M6 contract request).
+        // `:core:design` reads "now" and the zone from :data's clock.
         val kvittClock = KvittClock({ Instant.fromEpochMilliseconds(clock.nowMillis()) }, TimeZone.of(clock.zone().id))
         setContent {
             KvittTheme {