IAV-793/ Add wiki management and free credits features

This Merge Request introduces wiki management functionality and a free credits feature, aimed at improving both user experience and overall system flexibility. It also includes a set of UI enhancements to ensure visual consistency and a more polished, interactive interface.

Key Improvements

• Introduced centralized button styles with animated shiny hover effects
• Implemented a free credits management modal with a unified purple theme
• Added a free credits badge in the header with hover animations
• Updated the header to apply a non-transparent blurred background on scroll
• Enhanced agent selection by replacing the standard select with an Autocomplete component supporting avatar tags
• Applied shiny hover effects to video cards and all interactive buttons
• Unified modal color themes by standardizing on purple instead of mixed red/yellow styles
• Improved confirmation dialogs and modal close buttons to align with the global theme

This update ensures a more cohesive UI, improved usability, and a consistent visual identity across the application.