Feature/wal 280 - Fix double retrieval of the offer request

[SuperBatata]

This pull request introduces a credential offer caching mechanism to optimize the credential issuance flow and reduce redundant network requests. The main changes include the addition of a thread-safe cache for credential offers, integration of this cache into the credential offer resolution logic, and updates to the exchange controller to utilize the cache.

Credential Offer Caching:

• Added a new CredentialOfferCache singleton object that uses a ConcurrentHashMap to store and retrieve CredentialOffer instances by key, providing thread-safe caching functionality.

Credential Offer Resolution Optimization:

• Updated the credential offer resolution logic in IssuanceService to first check the cache for a resolved offer, then attempt to parse a JSON offer, and finally fall back to the legacy URI resolution if needed. This avoids unnecessary network requests and improves performance.

Controller Integration:

• Modified the ExchangeController to cache the resolved credential offer against the original request string immediately after parsing, ensuring subsequent accept operations can retrieve the offer from the cache.
• Imported the new CredentialOfferCache in the ExchangeController file to support caching functionality.

Minor Cleanup:

• Removed an unused import (withLoggingContext) from the ExchangeController for code cleanliness.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[JakeFernandes98]

We should avoid storing state in memory here as it doesn't scale well with multiple instances of the service running. Could you provide config options for in memory or using the DB?