fix(calendars): apply scaffold padding so month/week/day headers and collections list don't render behind the top app bar

The DisappearingScaffold places content at y=0 by design (so feeds scroll
behind the bar) and exposes the bar height via [LocalDisappearingScaffoldPadding]
for inner scrollables to consume. The static-headered grid views and the
collections list weren't reading that local, so:

- The week view's WeekStrip (day-number row) rendered behind the top bar.
- The month/year title and grid header sat behind the bar similarly.
- The collections LazyColumn's first card was clipped under the bar.

Fix:
- Add a small `Modifier.disappearingScaffoldPadding()` helper that applies
  the local padding. Month/week/day views opt in with one line.
- Collections LazyColumn uses `rememberFeedContentPadding(FeedPadding)`
  so cards inset on first render but still scroll behind the bar (matching
  the feed view's behaviour).

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

@@ -56,11 +56,13 @@ import com.vitorpamplona.amethyst.commons.ui.feeds.FeedState
 import com.vitorpamplona.amethyst.model.LocalCache
 import com.vitorpamplona.amethyst.model.Note
 import com.vitorpamplona.amethyst.ui.feeds.RefresheableBox
+import com.vitorpamplona.amethyst.ui.layouts.rememberFeedContentPadding
 import com.vitorpamplona.amethyst.ui.navigation.navs.INav
 import com.vitorpamplona.amethyst.ui.navigation.routes.Route
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.AccountViewModel
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.video.UserCardHeader
 import com.vitorpamplona.amethyst.ui.stringRes
+import com.vitorpamplona.amethyst.ui.theme.FeedPadding
 import com.vitorpamplona.quartz.nip01Core.core.Address
 import com.vitorpamplona.quartz.nip52Calendar.appt.day.CalendarDateSlotEvent
 import com.vitorpamplona.quartz.nip52Calendar.appt.time.CalendarTimeSlotEvent
@@ -102,7 +104,12 @@ private fun CollectionsBody(
     nav: INav,
 ) {
     val items by loaded.feed.collectAsStateWithLifecycle()
-    LazyColumn(modifier = Modifier.fillMaxSize()) {
+    LazyColumn(
+        // Reserve top space for the surrounding [DisappearingScaffold]'s top bar — without this
+        // the first card scrolls under it on the initial render.
+        contentPadding = rememberFeedContentPadding(FeedPadding),
+        modifier = Modifier.fillMaxSize(),
+    ) {
         items(items.list, key = { it.idHex }) { note ->
             CalendarCollectionCard(note, accountViewModel, nav)
         }

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

@@ -95,6 +95,7 @@ fun CalendarDayView(
         modifier =
             Modifier
                 .fillMaxSize()
+                .disappearingScaffoldPadding()
                 .calendarSwipeNavigation(
                     key = visibleEpochDay,
                     onSwipeLeft = { visibleEpochDay = visibleDate.plusDays(1).toEpochDay() },

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

@@ -106,6 +106,7 @@ fun CalendarMonthView(
         modifier =
             Modifier
                 .fillMaxSize()
+                .disappearingScaffoldPadding()
                 .calendarSwipeNavigation(
                     key = visibleYear to visibleMonthValue,
                     onSwipeLeft = {

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

@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.ui.screen.loggedIn.calendars
+
+import androidx.compose.foundation.layout.padding
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.composed
+import com.vitorpamplona.amethyst.ui.layouts.LocalDisappearingScaffoldPadding
+
+/**
+ * Applies the surrounding [com.vitorpamplona.amethyst.ui.layouts.DisappearingScaffold]'s reserved
+ * top/bottom space as padding. The scaffold places content at y=0 by design — it lets feeds
+ * scroll *behind* the disappearing bar — but the month/week/day views are static-headered grids,
+ * so without this modifier the grid header would render under the top app bar. Outside a
+ * scaffold the local default is zero and the modifier is a no-op.
+ */
+@Composable
+fun Modifier.disappearingScaffoldPadding(): Modifier =
+    composed {
+        val padding = LocalDisappearingScaffoldPadding.current
+        this.padding(padding)
+    }

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

@@ -96,6 +96,7 @@ fun CalendarWeekView(
         modifier =
             Modifier
                 .fillMaxSize()
+                .disappearingScaffoldPadding()
                 .calendarSwipeNavigation(
                     key = weekStartEpochDay,
                     onSwipeLeft = {