Miscellaneous Ragnarok Fixes
The following tweaks are included based on observations from stagenet test of BNB ragnarok and re-audit while making changes:
- Only allow synth exit swaps of synth to the corresponding L1 during ragnarok
- Disallow streaming synth exits during ragnarok
- Withdraw savers as non-streaming during ragnarok
- Clear all corresponding loan records during ragnarok
- Also remove corresponding synth and derived asset pools for gas assets
The separate fixes are organized into commits so this can be merged without squash to preserve clear history without independent reviews.