Attach any file, take shares from other apps, and survive a backwards highlight

Attachments were images only. Now any file can be attached: from the file
chooser behind the "+" menu, or from Android's share sheet, which the app
is now in. An image still goes to the model as a picture; anything else is
stored under its own name (`<hex>-<name>`, cleaned by `safe_file_name`)
and the Claude driver ends the message with `Attached file: /abs/path`,
since the CLI reads files by path and a model cannot be shown a trace. The
user-message field is renamed `images` -> `attachments` on both sides,
with a serde alias reading the rows written before. A share arrives before
anyone has said which session it is for, so it is held in AppRoot with a
banner on the list until a session takes it; an open session takes it at
once. Unreadable shares are reported beside the composer, not thrown.

The tool card crashed the app when opened on a command holding a quoted
glob such as `-path '*/.git/*'`: highlights 1.1.0's shell lexer answers
`x '*/a/*'` with a span whose end is before its start, and AnnotatedString
refuses the range. Such spans are dropped; the library is the place for
the fix. The echo driver gains `/bash <command>` so a card with a given
command can be produced on the emulator.

ui-sandbox.sh's token salvage read the tokens block's close only at a line
start, ran past the compact `),],` the server writes, and copied `setups`
into the new config twice, which the server then refused.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

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

@@ -129,7 +129,7 @@ sealed class TranscriptUnit {
         val first: Boolean,
         val last: Boolean,
         /** The message's attachments, drawn under the words -- so only the last slice has any. */
-        val images: List<String>,
+        val attachments: List<String>,
         override val gap: Dp,
     ) : TranscriptUnit() {
         override val key: Any
@@ -211,7 +211,7 @@ fun transcriptUnits(
                         chunk,
                         first = at == 0,
                         last = at == chunks.lastIndex,
-                        images = if (at == chunks.lastIndex) item.images else emptyList(),
+                        attachments = if (at == chunks.lastIndex) item.attachments else emptyList(),
                         gap = if (at == 0) rowGap else 0.dp,
                     )
             }