aisman

Session 153, Step 13: Fix user story split view scroll sync feedback loop
- AIM-2848 Fix user story split view scroll sync feedback loop
- AIM-2870 Fix host file creation error on live — absolute path leaks through displayPath

Outcome:
AIM-2848 — overrode `scroll-behavior: smooth` (from `.aim-md-preview` CSS) to `auto` on preview elements during split mode so programmatic `scrollTop` jumps instantly. Applied to all split-mode entry/exit paths in `dashboard.js` and `dashboard-workflow.js`.

AIM-2870 — replaced `AimFS.writeFile` with `_safeWriteFile` helper that handles OPFS `TypeMismatchError` by detecting stale file entries where directories should be, removing them, and retrying. Applied to both the "Create file" button handler and the save flow in `dashboard-settings.js`.