refactor(tests): reformat code and update dependency management

- Reorganized import statements in adapter tests for better readability
- Replaced or_insert_with(Vec::new) with or_default() in test closures
- Updated Cargo.lock with new dependency versions and checksums
- Added TLS features to tonic dependency configuration
- Included sqlx, chrono, and uuid dependencies with specific features
- Added jsonwebtoken and arc-swap as project dependencies
- Reformatted assertion statements to comply with line length limits
- Adjusted base64 import order in engine codec module
- Updated protobuf include statement formatting

repo/message_repo.rs

@@ -0,0 +1,27 @@
+//! Message repository — struct definition and pool accessor.
+//!
+//! CRUD operations are split across `message_create.rs` (writes)
+//! and `message_query.rs` (reads) as separate `impl` blocks.
+
+use sqlx::PgPool;
+
+/// Repository for message CRUD operations.
+///
+/// All queries use parameterized statements via sqlx.
+/// IDs are UUID v7 (time-ordered) for efficient cursor pagination.
+#[derive(Clone)]
+pub struct MessageRepo {
+    pool: PgPool,
+}
+
+impl MessageRepo {
+    /// Create a new repository backed by the given connection pool.
+    pub fn new(pool: PgPool) -> Self {
+        Self { pool }
+    }
+
+    /// Access the inner `PgPool` for advanced queries.
+    pub fn pool(&self) -> &PgPool {
+        &self.pool
+    }
+}