ai: apply changes for #870 (2 review threads)

Addresses:
  - #3601040104 at .bot/prompts/engineer-followup/system.md:31
  - #3601040111 at .bot/prompts/engineer/system.md:121

Signed-off-by: peco-engineer-bot[bot] <peco-engineer-bot[bot]@users.noreply.github.com>

Author: peco-engineer-bot[bot]

.bot/prompts/engineer-followup/system.md

@@ -28,12 +28,11 @@ Your job:
 
 Repo facts you need:
   - `poetry`-managed, Python 3.8+; `poetry install --all-extras` has run on the
-    runner, and the live-warehouse connection env is set — so both
-    `poetry run python -m pytest tests/unit` (mocked) AND `tests/e2e` (live) are
-    runnable. If a reviewer's ask is about connector behavior that only an E2E test
-    can verify, add/adjust a `tests/e2e` test on the RIGHT backend for the change
-    (Thrift default / `use_sea=True` / `use_kernel=True` — see CONTRIBUTING.md →
-    "Backends and test tiers"), don't settle for a mocked unit test.
+    runner, but this follow-up job wires NO live-warehouse connection env — so
+    only `poetry run python -m pytest tests/unit` (fully mocked) runs here. Do
+    NOT run or add `tests/e2e` (needs live credentials this job does not have).
+    If a reviewer's ask can only be verified by an E2E test, say so and mark the
+    thread blocked rather than adding an e2e test that cannot run here.
   - Source is under `src/databricks/sql/`; unit tests under `tests/unit/`.
     Follow `CONTRIBUTING.md`: PEP 8 with a 100-char line limit, type hints where
     the surrounding code uses them. This is a widely-consumed connector — keep

CONTRIBUTING.md

@@ -146,13 +146,14 @@ The suites marked `[not documented]` require additional configuration which will
 
 #### Backends and test tiers
 
-The connector has **two execution backends**, selected per connection. When you
+The connector has **three execution backends**, selected per connection. When you
 reproduce or fix a bug, use the backend the bug is actually on — a Thrift bug won't
-reproduce on a kernel connection, and vice versa:
+reproduce on a SEA or kernel connection, and vice versa:
 
 | Backend | Select via (connect kwarg / `extra_params`) | Where its tests live |
 | --- | --- | --- |
 | **Thrift** (default) | *(nothing — the default path)* | the general `tests/e2e` suite (the `{}` parametrize case) and mocked `tests/unit` |
+| **SEA** (Statement Execution API) | `use_sea=True` | the general `tests/e2e` suite (the `{"use_sea": True}` parametrize case, e.g. `tests/e2e/test_driver.py`) and mocked `tests/unit` |
 | **Kernel** (Rust, optional) | `use_kernel=True` | the dedicated `tests/e2e/test_kernel_backend.py` / `test_kernel_tls.py`, plus the offline routing test `tests/unit/test_session.py -m realkernel` |
 
 Notes that matter when running the suite: