Cleanup only, no behaviour change (ruff clean + pytest 193):
- keep the whole OAuth scope vocabulary together in app/auth.py: the bundles
(BASE_SCOPES/READ_SCOPES/WRITE_SCOPES/_YOUTUBE_SCOPES) move back next to the
atoms (READ_SCOPE/WRITE_SCOPE) as core; routes/auth.py imports the bundles it
needs instead of rebuilding them from the atoms.
- compact the const groups the split generator spread out (the six rate
limiters, the TTLs, the demo/scope constants) back into blocks.
peter
ac6383e92c