Show what was remembered as a note, not as markup

Claude Code marks a sentence taken from its stored memory by wrapping it
in `<cc-memory filenames="...">`. Markdown has nothing to say about that,
so it arrived as literal angle brackets mid-sentence and read as the
model having emitted broken HTML. It is the opposite: a claim about
where something came from, and "I was told this before" and "I worked
this out just now" are different things the reader could not otherwise
tell apart.

Each one becomes a card naming the files it came from, with the prose
either side of it left as prose. Named rather than merely tinted, since
a colour can say "this one is different" but not what kind of different.

A tag still arriving is left alone: streaming means the closing half may
be seconds away, and a half-written marker is not a marker yet.

Verified on the emulator with two notes in one message, one of them
citing two files, and prose before, between and after.

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

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

@@ -578,7 +578,7 @@ fun SessionScreen(
                 items(items.asReversed()) { item ->
                     when (item) {
                         is TranscriptItem.UserMsg -> UserBubble(item.text)
-                        is TranscriptItem.AssistantMsg -> MarkdownText(item.text)
+                        is TranscriptItem.AssistantMsg -> AssistantMessage(item.text)
                         is TranscriptItem.ToolRun ->
                             ToolCard(
                                 tool = item,