Add FREE AI Providers: OpenRouter, Xiaomi MiMo, GLM, SiliconFlow

[rheyn4566]

🚀 Feature: Add FREE AI Providers

I've implemented support for new AI providers with FREE models for coding!

🔗 My Fork with Complete Code:

👉 https://github.com/rheyn4566/android-code-studio/tree/add-free-ai-providers

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✨ New Providers Added:

Provider	Models	Cost
OpenRouter	40+ models	🆓 Many FREE
Xiaomi MiMo	MiMo-V2-Flash (309B)	Xiaomi API
GLM (智谱AI)	glm-4-flash, codegeex-4	🆓 Free tier
SiliconFlow	Qwen, DeepSeek, Yi	🆓 FREE

🆓 FREE Models for Users:

• qwen/qwen-2.5-coder-7b-instruct:free (OpenRouter)
• Qwen/Qwen2.5-Coder-7B-Instruct (SiliconFlow)
• glm-4-flash (GLM)
• deepseek-ai/DeepSeek-V2.5 (SiliconFlow)

📁 Files Changed:

• ✅ Created 4 new provider classes
• ✅ Updated Agents.kt, AIAgentManager.kt, ApiKey.kt
• ✅ Added preferences UI and string resources

This gives users access to FREE AI models! 🎉

Would love to see this in the app! 🙏