✨ Update README with configuration details, add default test configuration, and implement TelegramMapper tests. Enhance message processing to set timestamps and improve error handling in the processor. Refactor NATS consumer configuration and ensure proper handling of message attributes.

README.md

@@ -70,6 +70,9 @@ psql -U postgres -f internal/repository/telegrams.ddl
 
 Configuration is loaded from TOML files and environment variables. The configuration file should be located at `configs/config.{env}.toml` where `{env}` is determined by the `GO_ENV` environment variable (defaults to `dev`).
 
+- `nats.url` and `nats.stream` are required (the latter defaults to `TELEGRAM` when omitted).
+- `subscription.topic` is optional; when not provided the application subscribes to `telegram.>`.
+
 ### Configuration Structure
 
 ```toml
@@ -92,6 +95,7 @@ ack_wait = "30s"
 max_ack_pending = 1024
 
 [subscription]
+# Optional. Defaults to "telegram.>" when omitted.
 topic = "telegram.serial"
 
 [publisher]
@@ -110,6 +114,10 @@ monitor_interval = "30s"
 [log]
 level = "info"
 format = "json"
+
+### Timeouts and Ack Wait
+
+`[timeouts]` is optional, but if you plan to tune JetStream redelivery you should set `timeouts.ack_wait` and/or `[nats.consumer].ack_wait`. When neither is specified the application defaults both values to `30s`, ensuring predictable redelivery timing.
 ```
 
 ### Environment Variables
@@ -472,6 +480,8 @@ Logs include contextual information:
 
 - **Batch Processing**: Messages are processed in configurable batches (default: 50)
 - **Database Inserts**: Uses PostgreSQL `COPY FROM` for efficient batch inserts
+  via `Repository.InsertBatch`. The default processor issues single inserts,
+  but you can switch to buffered batches in high-throughput deployments.
 - **Connection Pooling**: Configurable PostgreSQL connection pool
 - **JetStream**: Reliable message delivery with automatic retries