Refactor and update test projects, remove obsolete tests, and upgrade dependencies

- Deleted obsolete test files for SchedulerAuditService and SchedulerMongoSessionFactory.
- Removed unused TestDataFactory class.
- Updated project files for Mongo.Tests to remove references to deleted files.
- Upgraded BouncyCastle.Cryptography package to version 2.6.2 across multiple projects.
- Replaced Microsoft.Extensions.Http.Polly with Microsoft.Extensions.Http.Resilience in Zastava.Webhook project.
- Updated NetEscapades.Configuration.Yaml package to version 3.1.0 in Configuration library.
- Upgraded Pkcs11Interop package to version 5.1.2 in Cryptography libraries.
- Refactored Argon2idPasswordHasher to use BouncyCastle for hashing instead of Konscious.
- Updated JsonSchema.Net package to version 7.3.2 in Microservice project.
- Updated global.json to use .NET SDK version 10.0.101.

docs/modules/excititor/operations/graph-linkouts-implementation.md

@@ -26,7 +26,7 @@
 - `vex_observations` indexes:  
   - `{ tenant: 1, component.purl: 1, advisoryId: 1, source: 1, modifiedAt: -1 }`  
   - Sparse `{ tenant: 1, component.purl: 1, status: 1 }`
-- Optional materialized `vex_overlays` cache: unique `{ tenant: 1, purl: 1 }`, TTL on `cachedAt` driven by `excititor:graph:overlayTtlSeconds` (default 300s).
+- Optional materialized `vex_overlays` cache: unique `{ tenant: 1, purl: 1 }`, TTL on `cachedAt` driven by `excititor:graph:overlayTtlSeconds` (default 300s); payload must validate against `docs/modules/excititor/schemas/vex_overlay.schema.json` (schemaVersion 1.0.0). Bundle sample payload `docs/samples/excititor/vex-overlay-sample.json` in Offline Kits.
 
 ## Determinism
 - Ordering: input PURL order → `advisoryId` → `source` for linkouts; overlays follow input order.