As mentioned above, this is not a specific coding language but rather a syntax used to define file paths and locations.
Looking at the last entry as a project, it refers to a project file used by Proteus. Proteus is commonly used for designing electronic circuits and creating simulations for microcontroller-based projects -
PCB Design & Simulation[
^]
Whether this might lead to a clue of an official language used somewhere in any of the files, no idea!