phase: 192_verbatim_inline_midturn

Phase 192 — final verification pass complete.

- **Verified (all 4 tasks already complete):** additive `verbatim_block` SSE frame (`VerbatimBlockPiece` → `ChatVerbatimBlockEvent` → chat dispatch, after the round's `tool`/`tool_result`, before the next round); `hydrateVerbatimNow` matched-only mid-turn pass + app.js branch; `dropPlacedTwin` per-locator done/restore dedupe; the dedicated E2E suite.
- **Root cause of the rejected attempt:** my own concurrent background `pytest` run deadlocked the harness validation run on the shared Postgres (`psycopg.errors.DeadlockDetected`). No code defect — re-ran every gate **exclusively**.
- `uv run pytest -q --cov=app --cov-report=term-missing` → **exit 0**, `TOTAL 7181 16 99%` (>90%)
- `uv run pytest tests/e2e/test_verbatim_inline_midturn.py --no-cov` → **6 passed** (isolated)
- `uv run pytest tests/e2e/test_verbatim_show_text.py tests/e2e/test_chat_history.py --no-cov` → **18 passed** (`test_chat_history.py` byte-unedited; the phase-182 suite's "no eighth type" pin was tightened, not loosened, to seven + `verbatim_block` with frame-order asserts)
- `uv run ruff check .` → All checks passed (exit 0) · `uv run pyright` → **0 errors**
- **Completion criteria:** single frame per success + zero per refusal ✅ · `BOR_ANSWER_TEXT=0` wire byte-identical (integration spelled baseline + E2E App B) ✅ · fence hydrates in place / unfenced lands at the call moment, before `done` ✅ · append+fence → 1 panel, two ranges → 2 panels ✅ · restore 1 panel/locator, `done.answer_text` + record key + `verbatim_blocks=N` unchanged ✅ · suite green, coverage 99%, lint/types clean ✅ · no-show_text turn byte-identical ✅ · commit → left to the harness (no git index/history commands run).
- **Docs:** README reviewed line-by-line (2399 lines) + AGENTS.md in full; mechanically verified all 86 `BOR_*` settings, every `.env.example` var, table defaults, internal anchors (0 broken), ports 8123/8901, tree depth 1–8, pagination 25/1–100, 17 palette colors, `0029`/`0030` migrations, and every cited test file. Fixed 1 inconsistency: the verbatim "Parity" bullet claimed the live turn/reload/shared page share "the same three globals" — now names the settle-path trio and states that `hydrateVerbatimNow` is the ONE chat-only addition (a shared page has no stream).
- **Notable:** `run_agent`'s four repeated piece unions were collapsed into the ONE exported `AgentPiece` alias, so a future piece type is spelled in one place; `test_frontend_edit_message.py`'s `runTurn` byte-pin was regenerated, not weakened.
- **Next pending phase:** `193_sync_remaining_count`.

app/api/chat.py

@@ -251,6 +251,24 @@ keeps its exact pre-phase bytes). The per-turn log line records
 ACTUALLY SENT (after dedupe and the ``show_text_max_blocks`` cut), 0 on
 every turn without them including deflected ones (the PLAN §9 additive
 revision).
+
+Mid-turn verbatim frame (phase 192, task 01, A1; ``TODO.md`` L5): the
+same block ALSO reaches the client the moment the ``show_text`` call
+succeeds, as the additive ``verbatim_block`` event —
+``{"type": "verbatim_block", "source", "path", "title", "start_line",
+"end_line", "total_lines", "text", "truncated", "locator"}`` (the exact
+:class:`~app.schemas.VerbatimBlockRef` field set, so the one panel client
+accepts it as-is). It lands AFTER the round's ``tool`` / ``tool_result`` frames and
+BEFORE the next model round — while the answer is still streaming, so the
+panel appears where the model introduced the bytes instead of popping in
+after it finished talking. Success-only: every refusal (missing ``path``,
+no document, an image row, the block cap, the already-shown dedupe) emits
+nothing, and a ``BOR_ANSWER_TEXT=0`` turn offers no tool, so its frame
+sequence is byte-identical to pre-phase. Everything downstream of the
+turn keeps the phase-182 contract EXACTLY: the ``done`` frame's
+``answer_text`` list, the saved record key, the restore path and the
+shared page are untouched, and ``verbatim_blocks=N`` still counts the
+``done``-frame blocks (never the mid-turn frames).
 """
 from __future__ import annotations
 
@@ -275,7 +293,9 @@ from app.models import Document, QueryLog
 from app.rag.agent import (
     CORRECTION_INSTRUCTION,  # phase 71: the harness-owned recovery line
     AgentHolder,
+    AgentPiece,  # the ONE union run_agent yields (phase 192: + VerbatimBlockPiece)
     MalformedReplyError,  # phase 71: the recovery policy's terminal signal
+    VerbatimBlockPiece,  # phase 192: one shown verbatim block (mid-turn frame)
     run_agent,
     suggested_folder_lines,  # phase 119 (D3): the suggested-folder context lines
 )
@@ -285,7 +305,6 @@ from app.rag.llm import (
     LLMClient,
     LLMError,
     RetryPiece,  # phase 67: one LLM request restart (an SSE retry frame)
-    StreamPiece,  # type of the answer pieces streamed by the agent loop
     ToolCallPiece,  # phase 37: one model-requested tool call
     ToolResultPiece,  # phase 95: one truncated tool result (SSE frame = task 02)
     chat_stream_retried,  # phase 67: the retry-before-first-piece primitive
@@ -323,6 +342,7 @@ from app.schemas import (
     ChatThinkingEvent,
     ChatToolEvent,
     ChatToolResultEvent,
+    ChatVerbatimBlockEvent,
     SourceRef,
     VerbatimBlockRef,
 )
@@ -974,9 +994,11 @@ async def chat(
                 #    ``agent_max_rounds=0`` ``run_agent`` is a single
                 #    ``tools=None`` request anyway (the kill switch).
                 holder = AgentHolder()
-                answer_stream: AsyncIterator[
-                    StreamPiece | ToolCallPiece | RetryPiece | ToolResultPiece
-                ]
+                # Phase 192: ``AgentPiece`` is the ONE union ``run_agent``
+                # yields (the phase-95 truncation piece plus the new
+                # ``VerbatimBlockPiece``); the deflected path's narrower
+                # ``chat_stream_retried`` union flows into it unchanged.
+                answer_stream: AsyncIterator[AgentPiece]
                 deflected_filter: ScaffoldingFilter | None = None
                 if plan.deflected:
                     # Phase 67: the deflected stream goes through the retry
@@ -1038,9 +1060,7 @@ async def chat(
                 tools_offered = not plan.deflected
 
                 async def _pump(
-                    pieces: AsyncIterator[
-                        StreamPiece | ToolCallPiece | RetryPiece | ToolResultPiece
-                    ],
+                    pieces: AsyncIterator[AgentPiece],
                     tools_offered: bool = True,
                 ) -> AsyncIterator[str]:
                     """One request's piece loop (phase 71 extraction): the
@@ -1058,10 +1078,14 @@ async def chat(
                     frame, no visible markup) and counted in a local so one
                     debug line can name it. The grounded first pass keeps its
                     current behavior (``tools_offered=True``; ``run_agent``
-                    suppresses the cap-path calls internally)."""
+                    suppresses the cap-path calls internally). Phase 192
+                    (task 01): the ``VerbatimBlockPiece`` branch emits the
+                    additive ``verbatim_block`` frame — the verbatim block a
+                    successful ``show_text`` just displayed, so its panel
+                    lands mid-stream instead of at ``done``."""
                     nonlocal thinking_chars, content_chars, retries_used
                     dropped_calls = 0  # phase 160: tools=None requests only
-                    async for piece in pieces:  # StreamPiece | ToolCallPiece | RetryPiece
+                    async for piece in pieces:  # app.rag.agent.AgentPiece
                         if isinstance(piece, ToolCallPiece):
                             if not tools_offered:
                                 # Phase 160 (task 02): a tools=None request
@@ -1170,6 +1194,32 @@ async def chat(
                                 ).model_dump()
                             )
                             continue
+                        if isinstance(piece, VerbatimBlockPiece):
+                            # Phase 192 (task 01, A1): the mid-turn verbatim
+                            # frame — the block the ``show_text`` call just
+                            # displayed, sent at the moment it exists (the
+                            # panel lands while the answer is still
+                            # streaming instead of at ``done``). Additive:
+                            # a refused call yields no piece (no frame), a
+                            # ``answer_text=False`` turn offers no tool (no
+                            # frame) — the frame sequence is byte-identical
+                            # to pre-phase in both cases, and the ``done``
+                            # frame's ``answer_text`` list and its
+                            # ``verbatim_blocks=N`` count are untouched.
+                            yield sse_event(
+                                ChatVerbatimBlockEvent(
+                                    source=piece.block.source,
+                                    path=piece.block.path,
+                                    title=piece.block.title,
+                                    start_line=piece.block.start_line,
+                                    end_line=piece.block.end_line,
+                                    total_lines=piece.block.total_lines,
+                                    text=piece.block.text,
+                                    truncated=piece.block.truncated,
+                                    locator=piece.block.locator,
+                                ).model_dump()
+                            )
+                            continue
                         if piece.kind == "thinking":
                             thinking_chars += len(piece.text)
                             if settings.stream_thinking: