Document request-scoped MySQL cleanup

site/doc/pages/mysql_connect.txt

@@ -15,6 +15,8 @@ Establishes a connection to a MySQL server and returns a pointer to the connecti
 
 This connection handle is then used with helpers such as `mysql_query()`, `mysql_error()`, and `mysql_disconnect()`.
 
+MySQL handles are request-scoped framework resources. If a request exits without calling `mysql_disconnect()`, UCE closes any remaining MySQL handles during request cleanup. Call `mysql_disconnect()` when you want to close early, but never store a `MySQL*` in globals, sessions, or other state that can outlive the current request.
+
 :example
 MySQL* db = mysql_connect();
 print(db != 0 ? "connected to MySQL" : "no MySQL server reachable with these credentials", "\n");

site/doc/pages/mysql_disconnect.txt

@@ -10,7 +10,7 @@ m : pointer to an existing MySQL connection struct
 :content
 Closes an existing connection to a MySQL server.
 
-Call this when you are done using a `MySQL*` connection handle.
+Call this when you want to release a `MySQL*` connection handle before the request ends. UCE also closes any remaining MySQL handles automatically during request cleanup, including handles skipped by exceptions or fatal request recovery. A `MySQL*` is only valid inside the request that opened it; do not cache it across requests.
 
 :example
 MySQL* db = mysql_connect();