Tweaks and fixes throughout the project (#27)

This PR contains the work done to do a little bit of housekeeping pass across all packages and the Website service.

To provide further details about the work:
* Refreshed the READMEs and source documentation to match the current code;
* Tagged every test case consistently across the Infrastructure, Localization, Persistence, and Website test targets;
* Removed Website middleware tests now covered by Infrastructure's own suite;
* Conformed the `PrepareDB` method to Sendable;
* Relaxes the production Compose DATABASE_TLS default from require to prefer;
* Added Persistence test verifying the prefer posture falls back to plaintext connections.

Reviewed-on: rock-n-code/loud-amsterdam#27
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>

Packages/Persistence/Tests/Cases/Public/Enumerations/TLSTests.swift

@@ -1,9 +1,16 @@
+import Logging
+import MySQLNIO
+import NIOCore
+import NIOPosix
 import NIOSSL
 import Testing
 
 @testable import Persistence
 
-@Suite("TLS enumeration")
+@Suite(
+    "TLS enumeration",
+    .tags(.enumeration)
+)
 struct TLSTests {
 
     // MARK: Properties tests
@@ -25,4 +32,27 @@ struct TLSTests {
         #expect(configuration.bestEffortEquals(.makeClientConfiguration()))
     }
 
+    @Test
+    func `prefer falls back to plaintext when the server offers no TLS`() async throws {
+        // The fake server never advertises `CLIENT_SSL`, so this connection can only succeed by downgrading to
+        // plaintext — pinning the driver behavior the `prefer` posture relies on.
+        let server = try await PlaintextMySQLServer.start()
+        let tlsConfiguration = try #require(TLS.prefer.tlsConfiguration)
+        let connection = try await MySQLConnection.connect(
+            to: .init(ipAddress: "127.0.0.1", port: server.port),
+            username: "loud",
+            database: "loud",
+            tlsConfiguration: tlsConfiguration,
+            logger: Logger(label: "test"),
+            on: MultiThreadedEventLoopGroup.singleton.any()
+        ).get()
+
+        let isConnected = !connection.isClosed
+
+        try await connection.close().get()
+        try await server.stop()
+
+        #expect(isConnected)
+    }
+
 }

Packages/Persistence/Tests/Cases/Public/Methods/ProbeTests.swift

@@ -5,7 +5,10 @@ import Testing
 
 @testable import Persistence
 
-@Suite("Probe method")
+@Suite(
+    "Probe method",
+    .tags(.method)
+)
 struct ProbeTests {
 
     // MARK: Methods tests

Packages/Persistence/Tests/Cases/Public/Methods/ServiceTests.swift

@@ -5,7 +5,10 @@ import Testing
 
 @testable import Persistence
 
-@Suite("Service method")
+@Suite(
+    "Service method",
+    .tags(.method)
+)
 struct ServiceTests {
 
     // MARK: Methods tests