feat: Implement vulnerability token signing and verification utilities

- Added VulnTokenSigner for signing JWT tokens with specified algorithms and keys.
- Introduced VulnTokenUtilities for resolving tenant and subject claims, and sanitizing context dictionaries.
- Created VulnTokenVerificationUtilities for parsing tokens, verifying signatures, and deserializing payloads.
- Developed VulnWorkflowAntiForgeryTokenIssuer for issuing anti-forgery tokens with configurable options.
- Implemented VulnWorkflowAntiForgeryTokenVerifier for verifying anti-forgery tokens and validating payloads.
- Added AuthorityVulnerabilityExplorerOptions to manage configuration for vulnerability explorer features.
- Included tests for FilesystemPackRunDispatcher to ensure proper job handling under egress policy restrictions.

src/IssuerDirectory/StellaOps.IssuerDirectory/AGENTS.md

@@ -5,7 +5,7 @@ Manage trusted VEX issuer metadata, keys, and trust overrides used by the VEX Le
 
 ## Scope
 - Service `src/IssuerDirectory/StellaOps.IssuerDirectory` providing REST APIs and admin tooling for issuers, keys, trust weights, audit logs.
-- Integration with Excitator/VEX Lens/Policy Engine for signature verification and trust weighting.
+- Integration with Excitor/VEX Lens/Policy Engine for signature verification and trust weighting.
 - Tenant overrides, import of CSAF publisher metadata, and compliance logging.
 
 ## Principles
@@ -17,7 +17,7 @@ Manage trusted VEX issuer metadata, keys, and trust overrides used by the VEX Le
 
 ## Definition of Done
 - APIs documented, RBAC enforced, audit logs persisted.
-- Key verification integrated with VEX Lens and Excitator; rotation tooling delivered.
+- Key verification integrated with VEX Lens and Excitor; rotation tooling delivered.
 - Docs/runbooks updated with compliance checklist.
 
 ## Required Reading