* feat: add OAuth servers to conditional rendering logic for MCPPanel in SideNav
* feat: add startup flag check to conditional rendering logic
* fix: correct improper handling of failure state in reinitialize endpoint
* fix: change MCP config components to better handle servers without customUserVars
- removes the subtle reinitialize button from config components of servers without customUserVars or OAuth
- adds a placeholder message for components where servers have no customUserVars configured
* style: swap CustomUserVarsSection and ServerInitializationSection positions
* style: fix coloring for light mode and align more with existing design patterns
* chore: remove extraneous comments
* chore: reorder imports and `isEnabled` from api package
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Co-authored-by: Danny Avila <danny@librechat.ai>