feat: ai assistant support llm proxy server

[lixun910]

• ai assistant support llm proxy server
• update model list

[Copilot]

Pull Request Overview

This PR adds support for LLM proxy servers to the AI assistant by introducing provider-specific default base URLs and updating the model list. The changes enable dynamic switching between different AI providers while properly configuring their respective API endpoints.

• Introduces provider-specific default base URLs for multiple AI providers (OpenAI, Anthropic, Google, etc.)
• Updates the AI model configuration to use dynamic base URLs instead of hardcoded Ollama endpoints
• Generalizes the UI to support multiple providers instead of being Ollama-specific

Reviewed Changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/ai-assistant/src/config/models.ts	Adds provider default base URLs mapping and updates model lists with new versions
src/ai-assistant/src/reducers/index.ts	Updates initial configuration to use dynamic base URL from provider mapping
src/ai-assistant/src/localization.ts	Removes Ollama-specific language and makes base URL labels generic
src/ai-assistant/src/components/ai-assistant-config.tsx	Implements dynamic base URL switching and generalizes UI for all providers
src/ai-assistant/package.json	Updates @openassistant package versions from 0.5.13 to 0.5.17
examples/demo-app/package.json	Updates @openassistant package versions from 0.5.13 to 0.5.17

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