feat(toolkit): fallback to fal instead of cdn

[efiop]

cdn just like fal_v3 are cloudflare-based, so if r2 or cf have an outage they will both go down. fal is our own legacy one that had the same feature parity as cdn (lacking object lifecycle, multipart) but still useful for now.

[efiop]

ah, missing test for that repo, WIP.

[efiop]

Correction, we do in test_stability.

[chamini2]

and how does this behave when v3 fails in multipart?

[efiop]

@chamini2 Like failing to upload a part? It will retry a few times within fal_v3 then error out, then will try fal which doesn't support multipart so it might fail if the file is too large. This is the same as with cdn.

[chamini2]

@chamini2 Like failing to upload a part? It will retry a few times within fal_v3 then error out, then will try fal which doesn't support multipart so it might fail if the file is too large. This is the same as with cdn.

my question is, if it fails entirely on the multipart for v3, will it try to do multipart or single part to fal? can we make sure it makes the "right" decision of doing single part until multipart is handled correctly in fal

[efiop]

@chamini2 multipart is handled in particular implementation, fal doesn't support so it will never try multipart.

Again, this is exactly like with cdn that we've been using here.