Refactored `CookieNames.cs` to replace the `GetEnvelopeReceiverCookieName(string key)` method with new methods for extracting envelope receiver keys from cookie names:
- Added `GetEnvelopeReceiverKeyOrDefault` to extract keys or return `null` if the format is invalid.
- Added `TryGetEnvelopeReceiverKey` to attempt key extraction with a success flag.
Updated `DigitalData.Auth.Claims.csproj` to increment `Version`, `AssemblyVersion`, and `FileVersion` from 1.0.0 to 1.0.1, reflecting the new functionality.
Introduce a new static class `CookieNames` in the `DigitalData.Auth.Claims` namespace to centralize and standardize the construction of cookie names for envelope receiver tokens.
- Added `GetEnvelopeReceiverCookieName` methods to generate cookie names with or without a default cookie name.
- Updated `AuthController` to use the `CookieNames` helper for constructing cookie names, replacing direct concatenation logic.
- Improved maintainability and consistency of cookie naming conventions across the application.
