### What problem does this PR solve?
Fix:
- Use @ to avoid split by `_` in model_name.
- Verify api_key when add instance.
- Pop api_key in list intances response.
- Remove useless index.
- Sort providers, instances and models by name.
- Get `is_tools` from llm_factories.json
### Type of change
- [x] Bug Fix (non-breaking change which fixes an issue)
### What problem does this PR solve?
Now each model support region with different URL
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
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Signed-off-by: Jin Hai <haijin.chn@gmail.com>
### What problem does this PR solve?
Now user can use 'think mode' to chat with LLM
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
---------
Signed-off-by: Jin Hai <haijin.chn@gmail.com>
### What problem does this PR solve?
Introduce 5 new tables, including model groups and provider instance.
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
- [x] Refactoring
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Signed-off-by: Jin Hai <haijin.chn@gmail.com>
