Access and permissions management API and login page redesign

This release adds new API endpoints for RBAC-based access and permissions management, along with a redesigned login page featuring Speakeasy brand styling.

Features

• Access and permissions management API #1968  - Added new API endpoints for access and permissions management with an RBAC enforcement package. (Author: @tgmendes )
• Login page redesign #1962  - Revamped the login page with Speakeasy brand styling, a distributed platform diagram with Control Plane and Tools Platform sections, and updated copy. (Author: @simplesagar )

Bug fixes

• Fix authorization header clobbering #1973  - Fixed an issue where API key headers were overwritten when the client credentials exchange was unconfigured. (Author: @qstearns )
• Upgrade insights copilot model #1964  - Upgraded the insights copilot to claude-sonnet-4-5 and injected the current date into the system prompt for improved temporal context. (Author: @adaam2 )
• Fix skeleton flash on logout #1961  - Suppressed the loading shell skeleton flash on unauthenticated routes during logout. (Author: @adaam2 )