fix: normalize top nav bar title font sizes

Three top nav bar titles overrode the Material3 titleLarge default with
titleMedium, rendering ~16sp while every other top bar title inherits
~22sp. Drop the titleMedium override so the Calendar event detail and Git
repository (home + sub-screen) titles match the rest of the app.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019N7b8D4vBvafhG9eU7M9iJ

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/calendars/detail/CalendarEventDetailScreen.kt

@@ -138,7 +138,6 @@ fun CalendarEventDetailScreen(
                 title = {
                     Text(
                         text = stringRes(R.string.route_calendar_event_detail),
-                        style = MaterialTheme.typography.titleMedium,
                     )
                 },
                 navigationIcon = {

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/gitRepo/GitRepositoryHomeUi.kt

@@ -99,7 +99,6 @@ fun RepoTitleBar(
         Column(Modifier.weight(1f, fill = false)) {
             Text(
                 text = event?.name() ?: fallback,
-                style = MaterialTheme.typography.titleMedium,
                 fontWeight = FontWeight.SemiBold,
                 maxLines = 1,
                 overflow = TextOverflow.Ellipsis,

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/gitRepo/GitRepositoryScreen.kt

@@ -754,7 +754,6 @@ private fun TopBarTitle(
 ) {
     Text(
         text = event?.name() ?: fallback,
-        style = MaterialTheme.typography.titleMedium,
         fontWeight = FontWeight.SemiBold,
         maxLines = 1,
         overflow = TextOverflow.Ellipsis,