test(auto-dim): pin the minibuffer dim behavior, not just the setting

- The old assertion checked a value the module just set.
- It couldn't fail even if the fork inverted the flag.
- Three behavioral tests now drive real windows and minibuffer.
- One pins the working half, one the flag-is-t boundary.
- The third pins a known fork gap as an expected failure.

adob--rescan-windows ignores the flag, so a completion popup dims every
window. I handed that fix to the fork, which owns the code. When the fork
honors the flag, the pinned test reports an unexpected pass and can go.

Each test asserts the other window is still dimmed. Without that control,
three broken implementations look exactly like a working fix.

0 files changed, 0 insertions, 0 deletions