feat: Implement DefaultCryptoHmac for compliance-aware HMAC operations

- Added DefaultCryptoHmac class implementing ICryptoHmac interface.
- Introduced purpose-based HMAC computation methods.
- Implemented verification methods for HMACs with constant-time comparison.
- Created HmacAlgorithms and HmacPurpose classes for well-known identifiers.
- Added compliance profile support for HMAC algorithms.
- Included asynchronous methods for HMAC computation from streams.

etc/concelier.yaml.sample

@@ -12,6 +12,27 @@ storage:
   # Mongo command timeout in seconds.
   commandTimeoutSeconds: 30
 
+# PostgreSQL storage for LNM linkset cache (optional).
+# When enabled, the Link-Not-Merge linkset cache is stored in PostgreSQL
+# instead of MongoDB, providing improved query performance for large datasets.
+postgresStorage:
+  enabled: false
+  # PostgreSQL connection string. Required when enabled.
+  connectionString: "Host=localhost;Port=5432;Database=concelier;Username=concelier;Password=concelier"
+  # Command timeout in seconds.
+  commandTimeoutSeconds: 30
+  # Connection pool settings.
+  maxPoolSize: 100
+  minPoolSize: 1
+  connectionIdleLifetimeSeconds: 300
+  pooling: true
+  # Schema name for LNM tables.
+  schemaName: "vuln"
+  # Enable automatic migration on startup (set to false in production).
+  autoMigrate: false
+  # Path to SQL migration files. Required if autoMigrate is true.
+  # migrationsPath: "./migrations/concelier-postgres"
+
 plugins:
   # Concelier resolves plug-ins relative to the content root; override as needed.
   baseDirectory: ".."