QuickJS in GPAC

Base version is quickjs-2026-06-16 : https://github.com/bellard/quickjs/commit/04be246001599f5995fa2f2d8c91a0f198d3f34c

Modifications to QuickJS

• define CONFIG_VERSION in QuickJS.c
• patched for MSVC compil, based on https://github.com/horhof/quickjs/compare/master...samhocevar:task/msvc-support
• do not define CONFIG_STACK_CHECK (stack checking breaks multithread support)
• patched for exporting JS_AtomIsArrayIndex and JS_IsArrayBuffer
• patched for switch classID on object (for webGL named textures in GPAC)

Modifications to QuickJS-libc (‘os’ and ‘std’ modules)

• moved from pthread to GF_Thread in ‘os’ module
• Worker support for windows (patched js_os_poll)
• cleanup worker thread exit to avoid leaks
• patch js_std_loop to not run forever for main thread
• added MSVC support for most ‘os’ functions (most importantly exec, waitpid and kill)
• use gpac module loader