fix: id format for provider, model muxing rule

[peppescg]

Replaced id muxing dropdown using @ rather than : and replace the split logic using indexOf returning everything after separator as model name. The : is used by Ollama model. Actually the providers are using different model name format, we would thing to add a model_id for fix this.

[coveralls]

Pull Request Test Coverage Report for Build 13626612610

Details

• 4 of 4 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.06%) to 69.56%

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Totals
Change from base Build 13540948529:	-0.06%
Covered Lines:	864
Relevant Lines:	1178

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💛 - Coveralls

[peppescg]

Changed the actions/cache due actions/cache#1510