android: the board's Filters and drag-to-reorder, as on the web

Filters: a chip under the search bar opens a sheet with Has attachment, Shared
with me and tags (a note must carry all of them), applied as they are tapped,
with a count on the chip and a Clear beside it. Only the main board filters and
search spans everything, as on the web; opening another view starts it
unfiltered, a deleted tag drops out of the filters as it does from the lens, and
an empty filtered board says so.

Reorder: hold a card, then move it. The hold is the long press that opens the
card's menu, which closes as the card starts to move; lifting without moving
leaves the menu as before, and moving before the hold is a scroll. Cards trade
places live and the drop writes the order through the core's reorder, newly
exposed over the ffi as reorder_notes. Only on the plain main board, and only on
the same side of the pinned line, since the store sorts pinned first.

#5313.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

android/app/src/main/res/values/strings.xml

@@ -28,6 +28,15 @@
     <string name="board_empty_body">Tap + to start a note or a list. Everything stays on this device until you connect a server.</string>
     <string name="empty_search_title">No matches</string>
     <string name="empty_search_body">Nothing matched “%1$s”.</string>
+    <string name="empty_filtered_title">No matches</string>
+    <string name="empty_filtered_body">No notes match these filters.</string>
+    <string name="filters">Filters</string>
+    <string name="filters_count">Filters · %1$d</string>
+    <string name="filters_clear">Clear</string>
+    <string name="filters_show">Show only</string>
+    <string name="filters_has_attachment">Has attachment</string>
+    <string name="filters_shared_with_me">Shared with me</string>
+    <string name="filters_tags">Tagged with all of</string>
     <string name="empty_trash_title">Trash is empty</string>
     <string name="empty_trash_body">Deleted notes wait here before they are removed for good.</string>
     <string name="empty_archive_title">Nothing archived</string>