fix(vertexai): Imagen JPEG compression quality out of range warning

[cynthiajoan]

Description

Added a warning log message if a value outside the range [0, 100] is specified for the JPEG compression quality in ImagenImageFormat.jpeg(compressionQuality:). Values outside this range seem to be treated as 0 or 100 by the backend and were likely set by accident. See b/395693541 (Google internal) for more details.

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[natebosch]

Should we consider making this throw an Error? We could check with RangeError.checkValueInInterval which throws an appropriate RangeError when the value is invalid.

Are the reasons an author would prefer to ignore an invalid quality argument?

[cynthiajoan]

Should we consider making this throw an Error? We could check with RangeError.checkValueInInterval which throws an appropriate RangeError when the value is invalid.

Are the reasons an author would prefer to ignore an invalid quality argument?

I think because backend will still work based on b/395693541, so it doesn't have to be an error? From developer's perspective I can accept either scenario, also iOS/JS is treating this as a warning other than an error.

[natebosch]

I think because backend will still work

Matching the backend behavior is a good reason. SGTM.