feat(maestro): split tool groups on text boundaries

Tool rows interleaved with agent text now produce separate
collapsed groups instead of one per turn. The timeline reads
text → group → text → group, matching chronological order.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docs/STRUCTURED-VIEW.md

@@ -189,14 +189,17 @@ choices, not daemon ones.
   presentation for `Notice`. `Plan` is the exception: both clients omit it
   from the transcript; the TUI may show the current plan in its status line,
   while the web client deliberately has no stats or plan rail.
-- The web client groups two or more tool rows after the same `User` row into
-  one collapsed turn activity block. `AgentText` and `AgentThought` rows stay
-  outside the group as standalone transcript items — the operator sees all
-  reasoning without expanding. Resolved approval rows between tools are
-  absorbed into the group. The collapsed header reads "N tool calls · Label
-  'arg'" where the label and argument come from the last tool row's
-  `splitToolTitle` — the operator sees which command is current at a glance.
-  Opening the group reveals tool rows in chronological order.
+- The web client groups each contiguous run of two or more tool rows into a
+  collapsed activity block. An `AgentText` or `AgentThought` row between
+  tools splits them into separate groups, so the timeline reads
+  text → group → text → group rather than lumping every tool in a turn into
+  one box. Text and thought rows stay outside groups as standalone transcript
+  items — the operator sees all reasoning without expanding. Resolved
+  approval rows between tools within a run are absorbed into the group. The
+  collapsed header reads "N tool calls · Label 'arg'" where the label and
+  argument come from the last tool row's `splitToolTitle` — the operator
+  sees which command is current at a glance. Opening the group reveals tool
+  rows in chronological order.
 - The web client's user, agent, thought, tool-detail, and notice text blocks
   copy their complete source text when clicked or keyboard-activated.
 - The web client consumes `available_commands_update` notices as the live