* Fix system prompt variable color logic by removing unused variable type from switch statement and adding new types.
* Add workspace id, name and user id as default system prompt variables
* Combine user and workspace variable evaluations into a single if statment, reducing redundant code.
* minor refactor
* add systemPromptVariable expandSystemPromptVariables test cases
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Co-authored-by: timothycarambat <rambat1010@gmail.com>
