* test: keep structured chat free of Electron imports
* test: widen runtime Electron ratchet to structured chat
* test: check whole structured-chat directories for Electron imports
Cover src/main/{native-chat,claude,codex}, src/shared and every structured-*
or agent-session-* file under src/main/runtime, so new files are checked by
default. A lane that exists today now fails loudly if it goes missing; only
the not-yet-landed acp/ and provider-process/ may be absent.
Move the test-only file rule into one classifier shared with the
localization audit, so -test-<thing> helpers and test doubles no longer
enter the production gate.
* test: run the Electron-import CLI path in tests and retire may-be-absent lanes
Export main() so the real-tree tests exercise the entry list CI uses,
check every required lane for the missing-directory error, and fail once
acp/ or provider-process/ exists while still allowed to be absent.
Brennan Benson
508419f11e