* fix: don't drop pending tool-call-marker prefix on tool.started/run.done
The `filterBridgeToolCallMarkupDelta` filter holds back any text that
ends in a partial prefix of `[Calling tool:` (i.e. `[`, `[C`, `[Ca`,
..., `[Calling tool`) so it can decide whether the buffered chars are
the start of a tool-call markup block to be hidden, or just regular
text to be released by the next delta.
The bug: that "release on next delta" assumption breaks at TWO points:
1. **On `tool.started`**: the next chunk for this assistant message is
the tool call itself, NOT a follow-up text delta. Buffered chars
sit there forever and nothing flushes them — they vanish silently
from the user-visible stream.
2. **On run completion**: the code did
`state.bridgePendingToolCallMarkup = undefined` directly, dropping
any pending chars without forwarding them.
Both cases produce the user-visible symptom of "abrupt cuts in text
right before/after tool calls (terminal, read_file, write_file...)" —
1 to 13 characters disappear at exactly the boundary where the model
was emitting natural prose that happened to end with `[`.
The fix introduces `flushPendingToolCallMarkup(state)` and calls it:
- In the `tool.started` branch BEFORE recording the tool call, so the
buffered chars are appended to the open assistant message and emitted
as a normal `message.delta` to the client.
- At run-done BEFORE clearing the buffer, same flush path.
This is a pure recovery patch — no change to the marker detection
logic itself. If the buffer turns out to actually be a real
`[Calling tool: ...]` marker that just hasn't completed yet, that
case is still caught by the existing `markerIdx >= 0` branch in the
filter on the next delta. The only behavioral change is that the
"orphan" cases (text that ends with `[` but never becomes a marker)
are no longer dropped.
* fix bridge marker flush persistence
---------
Co-authored-by: Paulo Cavallari <paulocavallari@users.noreply.github.com>
ekko