fix(firebase_ai): Added InlineDataPart for File response in Gemini Api

[theshivamlko]

Description

Fixed parsing File response using InlineDataPart in developer/api.dart

Previously it was throwing error on Image generation via Gemin API, even image base64 response was received by app.
inlineData content part not yet supported

Related Issues

Issue fixed #17449
[firebase_ai] FirebaseAI.googleAI() Does not support generating images

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Breaking Change

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