fix(automation): consume and report the tail of a batch command line

`run_command_line` feeds the tokens after the command verb to the interactive
command and then terminates it as if Enter were pressed. Two gaps left a
headless caller unable to tell what actually happened.

In-place text editor takes over, remaining tokens were dropped
----------------------------------------------------------------
The `TEXT` content step hands over to the in-place editor, at which point the
command has already ended (`active_cmd` is `None`). The feed loop stopped
there, so the rest of the line — including the text itself — vanished:
`TEXT 0,0 5 0 hello` reported `completed` with `added: 0` and created nothing.
The tail is now typed into that editor and committed, and the commit is done
synchronously so its result is observable: `text_inline_commit()` returning
false leaves the tokens in `unconsumed` instead of reporting a successful line.
Dispatch the commit as a queued message instead and a failed commit would look
exactly like a good one — the text dropped, `added: 0`, `unconsumed: []`.

Only an editor this line opens is taken over, and after a successful commit the
line is closed with an escape: `TEXT` re-arms for the next line
(`open_next_line`), which would otherwise let the *next* batch line be eaten as
the next text position.

Leftover tokens are dropped
---------------------------
Any token no prompt ever asked for is recorded in `CommandLine::unconsumed` and
surfaced by the automation `run` response, so over-typed or misplaced input is
visible instead of silently ignored: `CIRCLE 0,0 5 9` reports
`"unconsumed": ["9"]` while a fully consumed line reports an empty list.

Pending surfaces are reported instead of `completed`
----------------------------------------------------
`run` now carries `blocked_by` — `"command"`, `"text_editor"`,
`"mtext_editor"`, `"modal:<Kind>"`, or `null` — and answers `waiting_input`
when something is still open rather than claiming `completed`.

`blocked_by` is attributed to the line that opened the surface: a condition and
its snapshot are taken before the command runs, so an editor left open by an
earlier line, another tab, or a startup dialog does not turn a finished command
into `waiting_input`. Without that attribution a caller polling for `completed`
would wait forever on someone else's editor. `docs/automation` documented
`waiting_input` as "more input is required", which is exactly what a pending
surface is; the two new fields are documented there as well.

Tests
-----
* `batch_text_line_creates_text_and_consumes_every_token` — the regression case
  creates exactly one `Text` entity and leaves nothing unconsumed.
* `multi_word_text_keeps_the_spaces` — asserts the committed string, so an
  off-by-one in the consumed index or a wrong join cannot pass.
* `run_reports_leftover_tokens_instead_of_dropping_them`.
* `text_without_content_reports_the_open_editor`.
* `a_stray_editor_is_not_hijacked_by_the_next_line` — the next line neither
  types into the stray editor nor inherits its blocker (`blocked_by: null`,
  `status: completed`).
* `a_command_still_waiting_is_named_as_the_blocker`.

Verified over the `--serve` protocol: `TEXT 0,0 5 0 hello world` → `completed`,
`added: 1`, and the entity really holds `hello world`; `TEXT 40,0 5 0` →
`waiting_input` + `blocked_by: "text_editor"`; the following `CIRCLE 0,0 5 9` →
`completed`, `blocked_by: null`, `unconsumed: ["9"]`; `LINE` → `waiting_input`
+ `blocked_by: "command"`.

Full lib suite: 1497 passed, 2 failed — both failures
(`io::plot_style::…named_tables_and_missing_files_get_a_reason`,
`scene::parametric_constraints::…arc_grips_drive_center_start_and_end_but_not_midpoint`)
reproduce on the unmodified tree; run with `LC_ALL=C` since several xref tests
otherwise fail on a non-English locale.

Known remaining gap, unchanged here: `MTEXT` / `HATCH` still answer `completed`
with `added: 0` in this path (they need interactive surfaces the feeder has no
tokens to fill). Reported separately in #1390.

docs/automation/README.md

@@ -138,7 +138,27 @@ Execute responses use `response_detail: "compact"` by default and return only th
 
 For unfamiliar or conditional commands, use `start`, then inspect `state.command` in every response. Its `accepts` array gives the valid MCP input kinds, `options` gives the current tokens, and `input_example` gives the next request shape. Add the current state fields and a new `request_id` to each step.
 
-Every `ocs_execute` request requires a caller-generated `request_id`. Reuse that ID only to retry the identical request after a timeout, together with the same session ID, document ID, expected revision, and selection. Commands report `waiting_input` while more input is required and asynchronous work remains `running` until its real callback finishes. Geometry stays in OpenCADStudio and its geometry kernel.
+Every `ocs_execute` request requires a caller-generated `request_id`. Reuse that ID only to retry the identical request after a timeout, together with the same session ID, document ID, expected revision, and selection. Commands report `waiting_input` while more input is required and asynchronous work remains `running` until its real callback finishes.
+
+A `run` reply also carries two fields that describe what happened to the line:
+
+* `blocked_by` — `null` when the command finished, otherwise what *this line*
+  left open and waiting: `"command"` (an interactive command), `"text_editor"`
+  (the in-place editor opened by the `TEXT` content step), `"mtext_editor"`, or
+  `"modal:<Kind>"` for a dialog. A surface that was already open when the line
+  started (an earlier line's editor, another tab, a startup dialog) is not
+  attributed to this line, so a caller polling for `completed` is never stuck
+  waiting on someone else's editor. `blocked_by` is set whenever `status` is
+  `waiting_input`.
+* `unconsumed` — the tokens of the line that no prompt ever asked for, in order.
+  A fully consumed line reports `[]`; `CIRCLE 0,0 5 9` reports `["9"]` because
+  the radius step ends the command. Over-typed input is reported instead of
+  being dropped on the floor.
+
+When a line ends at the `TEXT` content step (`TEXT 0,0 5 0 hello`) the text is
+typed into the in-place editor and committed, so the line behaves exactly as the
+same input typed into the GUI command line would: one `Text` entity, nothing
+unconsumed, and the command closed rather than left armed for a second line. Geometry stays in OpenCADStudio and its geometry kernel.
 
 `ocs_capture` defaults to the drawing viewport and a longest edge of 1600 pixels. Set `scope` to `window` for the full interface or change `max_dimension` between 256 and 4096.