⚡ Bolt: Optimize OllamaClient connection reuse

[google-labs-jules]

💡 What:

• Implemented persistent requests.Session in OllamaClient (core/ollama_client.py).
• Replaced individual requests.post calls with self.session.post in generate, chat, and stream methods.
• Refactored stream method to use the shared session while preserving specific headers for event streaming.

🎯 Why:

• Previously, every API call to Ollama established a new TCP connection (handshake overhead).
• For a local LLM client making frequent requests (chat, generation, streaming), this adds unnecessary latency.

📊 Impact:

• Eliminates TCP handshake latency for subsequent requests (measurable in milliseconds per request, significant for high-frequency interaction).
• Reduces system resource usage (socket creation/teardown).

🔬 Measurement:

• Verified using a reproduction script that mocks requests and confirms session.post is used instead of requests.post.
• Confirmed proper header handling in streaming requests.

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PR created automatically by Jules for task 3176438193679347593 started by @Rohith-Shimori

[google-labs-jules]

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