Development tools for Zephyr on STM32Workbench for Zephyr: VS Code extension to set up, build, flash and debug Zephyr applications on STM32.Devicetree manager: browse, edit and visualize Zephyr devicetree, STM32CubeMX-like for Zephyr.
Starting the debugging is part of the make-process, and the chip will only be reprogrammed, if something in your code changed.
You can simply press reset on your board to restart your debug-session.