workspace: record reason alias inline in run_loop

Added coverage/engine.md noting the inline-alias refactor and the
safety argument for the `state.status.reason` property access.

Co-authored-by: Ralphify <noreply@ralphify.co>

Author: 2 people

workspace/ralphs/improve-codebase/coverage/engine.md

@@ -0,0 +1,34 @@
+# `engine.py` coverage
+
+Valid at: c5ce11d
+
+## Recent changes
+
+- c5ce11d — inlined the `reason = state.status.reason` local in
+  `run_loop`.  The alias was read exactly once on the next line as the
+  `reason=` kwarg to `RunStoppedData(...)`.  Inlined to
+  `reason=state.status.reason` to match the chained-read style elsewhere
+  (e.g. `_IterationPanel._apply_assistant`'s `raw.get("message", {}).get("usage")`
+  after 52e0272).  Same Phase 4 inline-alias shape as ce487d3 (`text`),
+  52e0272 (`msg`), 497c028 (`agent`), fc5e1cb (`total_in`).
+  Safe: the immediately-preceding `if state.status == RunStatus.RUNNING:
+  state.status = RunStatus.COMPLETED` normalizes the status to a terminal
+  value, so `RunStatus.reason`'s ValueError guard (non-terminal) cannot
+  fire here.
+
+## Structure notes
+
+`run_loop` is the main loop orchestrator.  Its control-flow helpers
+(`_handle_control_signals`, `_wait_for_resume`, `_run_iteration`,
+`_delay_if_needed`) are each short and single-purpose.  `_run_iteration`
+splits into `_run_commands` → `_assemble_prompt` → `_run_agent_phase`.
+`_run_agent_phase` is the longest at ~80 lines but its branches map 1:1
+to the agent outcome tri-state (timed_out / success / failure) — no
+obvious extraction candidate without inventing synthetic abstractions.
+
+## Potential future wins (not yet taken)
+
+- None spotted.  The locals that survive in `_run_agent_phase`
+  (`duration`, `event_type`, `state_detail`, `ended_data`) all have
+  multiple uses and good names.  `_run_commands`'s `output` is mutated
+  before use.  `_run_iteration`'s `iteration` alias is used 4 times.

workspace/ralphs/improve-codebase/iterations.md

@@ -2,6 +2,8 @@
 
 One line per iteration: `<sha> <summary>`.
 
+c5ce11d refactor: inline `reason = state.status.reason` alias in `run_loop`'s `RUN_STOPPED` emit.  The local was read exactly once as the `reason=` kwarg to `RunStoppedData(...)` on the next line; collapsing to `reason=state.status.reason` matches the inline-alias pattern from ce487d3 (`text`) / 52e0272 (`msg`) / 497c028 (`agent`) / fc5e1cb (`total_in`).  Safe at this call site — the immediately-preceding `if state.status == RunStatus.RUNNING: state.status = RunStatus.COMPLETED` normalizes status to a terminal value (STOPPED / COMPLETED / FAILED), so the `RunStatus.reason` property's "non-terminal raises ValueError" guard cannot fire.
+
 3823019 refactor: narrow `line = escape_markup(data["line"])` scope past the early-return guard in `_on_agent_output_line` — the local was computed unconditionally inside `_console_lock` but only used on the `_IterationSpinner` branch; the `if not isinstance(target, _IterationSpinner): return` early-return path would have thrown the value away.  Moving the binding below the guard preserves exactly the same output (same escape_markup call, same f-string, same add_scroll_line) while skipping the wasted work whenever target is None or an _IterationPanel.  Same Phase 4 shape as 134078d (`name_col`), 7730dd4 (`secs`), ef176bf (`line_count`), 59b0e34 (`page`).  Pinned by the raw-line handling tests in test_console_emitter.py.
 
 ce487d3 refactor: inline `text` alias in `_output.py:collect_output` — the local was assigned from `ensure_str(stream)` and read exactly once on the next line as `parts.append(text)`.  Same alias-inline shape as fc5e1cb / 497c028 / 52e0272 — the `ensure_str` helper name already documents the decode step, so the intermediate binding was pure noise.  Tests in `test_output.py` cover the str, bytes, and stdout+stderr-newline-join paths.