Resolve Job inputs automatically in decorated flows

[Andrew-S-Rosen]

Closes #884.

What changed

• Convert Job and Flow values passed to jobs inside @flow-decorated functions into their output references automatically.
• Apply the conversion recursively to list, tuple, and dictionary inputs.
• Keep conversion limited to decorated-flow construction; runtime job execution is unchanged.
• Add regression tests for the minimal example from Feature request: automatic .output resolving in flow-decorated functions #884.

Why

The decorated-flow build context already collects delayed jobs, but downstream job construction retained whole Job objects as inputs. This produced an invalid job argument and required users to write .output explicitly. Replacing these values while the decorated flow is being built makes the shorthand behave as expected without changing job construction outside @flow.

[Andrew-S-Rosen]

@utf --- could I get your review when you have a moment? Thanks.

[gpetretto]

Hi @Andrew-S-Rosen,
I think this would be interesting. I have left a few cosmetic comments and one with a major concern.
In general, I don't expect this to conflict with #870

[Andrew-S-Rosen]

@gpetretto Thank you very much for the helpful review! I think I have addressed your comments. The buggy code you pointed out has since been removed entirely. There was an edge case I was trying to resolve (mentioned in #885 (comment)), but it is different than #884 and probably not sensible anyway. I have streamlined this PR to focus on the main issue at hand.