Instead of a standard 5-pin header please use the standard 10-pin (2x5 1.27mm header) ARM-SWD connector.
KICAD even has a symbol for it (Conn_ARM_JTAG_SWD_10).
If we are using the ST-Link V3 we could think about using their 14pin extended variant which adds an UART for "printf debugging" (Conn_ST_STDC14).
Instead of a standard 5-pin header please use the standard 10-pin (2x5 1.27mm header) ARM-SWD connector. KICAD even has a symbol for it (Conn_ARM_JTAG_SWD_10). If we are using the ST-Link V3 we could think about using their 14pin extended variant which adds an UART for "printf debugging" (Conn_ST_STDC14).