Test the library with different model providers

[kelsey-wong]

Including:
- Gemini
- Bedrock
- OpenAI
- Deepseek

[katwinkl3]

Gemini:
Not really a bug but gemini-1.5-flash fails with "models/gemini-1.5-flash-exp is not found for API version v1beta, or is not supported for generateContent" for me, but might be due to my account setup? gemini/gemini-2.0-flash-exp works fine for me. Also tested vertex_ai/gemini-2.5-pro and it works (should we support this?)
Bedrock:
Got a 'User: arn:aws:iam::.... is not authorized to perform: bedrock:InvokeModel on resource: ... with an explicit deny in an identity-based policy"}'
Deepseek:
Ran into the 'insufficient balance' err and my ramp card got declined so i cant verify if it works 🥲

[kelsey-wong]

@katwinkl3 did you use the instructions referenced in my jupyter notebook for testing the bedrock models? they worked for me in the past with the proper environment variables

[katwinkl3]

It should be my env set up! I saw your notebook cell so I assumed you had no trouble with the bedrock models