### 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)
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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>