Keep tool group keys unique across transcript

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

@@ -113,24 +113,27 @@ private fun groupRuns(
 ): List<TranscriptRow> {
     val rows = mutableListOf<TranscriptRow>()
     var run = mutableListOf<TranscriptItem.ToolRun>()
-    // The run being walked, and how many rows it has produced so far -- which is what decides the
-    // keys below.
+    // A run can occupy more than one non-adjacent piece, so claimed keys span the whole transcript
+    // rather than resetting at each piece.
     var runId: String? = null
-    var emitted = 0
+    val claimedKeys = mutableSetOf<String>()
 
     fun flush() {
         val first = run.firstOrNull() ?: return
-        // The first row a run produces keeps the run's name, which is the name that survives a page
-        // of history landing in front of it ([adoptRun]); losing it is the transcript stepping
-        // under whoever is reading. The pieces a call standing on its own cuts off the back of the
-        // run have no such name, so each takes its own first call's id, which is unique because a
-        // call id is. The run's name goes in front of it because the two can otherwise be the same
-        // string: the call a run was named after can itself be the one standing on its own.
-        val key = if (emitted == 0) first.runId else "${first.runId}/${first.id}"
+        // The first piece keeps the run's name, which survives a page landing in front of it
+        // ([adoptRun]). Later pieces qualify that name with their first call; the suffix is the
+        // final guard because a duplicate LazyColumn key takes down the whole screen.
+        var key = first.runId
+        if (!claimedKeys.add(key)) {
+            key = "${first.runId}/${first.id}"
+            var suffix = 2
+            while (!claimedKeys.add(key)) {
+                key = "${first.runId}/${first.id}/${suffix++}"
+            }
+        }
         rows +=
             if (run.size == 1) TranscriptRow.Single(first, key)
             else TranscriptRow.Tools(run.toList(), key)
-        emitted++
         run = mutableListOf()
     }
 
@@ -143,7 +146,6 @@ private fun groupRuns(
         if (call == null || call.runId != runId) {
             flush()
             runId = call?.runId
-            emitted = 0
         }
         when {
             call == null -> rows += TranscriptRow.Single(item)