Close a card by pressing its words, and let a selection be put away

A markdown paragraph took every tap that landed on its glyphs, so an opened
peer message or memory note could be shut anywhere except on the text --
which is most of it, and reads as a card that has stopped working. Measured
on the emulator: with a handler on the text the tap did nothing at all, and
with the handler removed the same tap shut the card. The words now do the
shutting, through a composition local, since the renderer composes those
paragraphs out of its own component table and there is nothing between the
card and them to pass a parameter through. The link handler is bounded by
the long-press timeout, so holding to select is not a tap.

The other half is the tap that puts a selection away, which used to shut
whatever card the words were in. The container clears the selection from
that same press, milliseconds before the card reads it, so the answer is
taken at composition instead -- what was true when the reader touched the
screen.

Selection colours are the app's own. Material's 40% of primary is a tint of
whatever is behind it, and over the near-black a code block sits on it
composited to a smudge, so selecting a line of code looked like nothing had
happened.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

app/androidApp/src/main/kotlin/com/example/aiapp/PeerMessage.kt

@@ -13,6 +13,7 @@ import androidx.compose.material3.CardDefaults
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalProvider
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.clip
@@ -87,9 +88,14 @@ fun PeerBlockRow(unit: TranscriptUnit.PeerBlock, replies: ParsedReplies, onToggl
             onPress = onToggle,
         )
     ) {
-        // The gap the card's own column used to provide between its heading and its prose, and
-        // between one block and the next -- inside the piece, so the card's fill runs through it.
-        MarkdownPiece(unit.text, unit.piece, replies, Modifier.padding(top = unit.spacing))
+        // The words shut the card too, and have to do it themselves -- see [LocalMarkdownTap].
+        // Without this the card closes everywhere except on the text, which is most of it.
+        CompositionLocalProvider(LocalMarkdownTap provides rememberMarkdownTap(onToggle)) {
+            // The gap the card's own column used to provide between its heading and its prose,
+            // and between one block and the next -- inside the piece, so the card's fill runs
+            // through it.
+            MarkdownPiece(unit.text, unit.piece, replies, Modifier.padding(top = unit.spacing))
+        }
     }
 }