feat: ✨ PostgreSQL connections opened by relspec set application_name by default to relspecgo/<version>

pkg/readers/pgsql/README.md

@@ -89,6 +89,10 @@ postgres://user@localhost/mydb?sslmode=disable
 postgres://user:pass@db.example.com:5432/production?sslmode=require
 ```
 
+By default, relspec sets `application_name` to `relspecgo/<version>` for PostgreSQL
+sessions so they are identifiable in `pg_stat_activity`. If you provide
+`application_name` in the connection string, your explicit value is preserved.
+
 ## Extracted Information
 
 ### Tables