Misleading description for "Max Threads"

**Your Godot version:** Godot v4.4.dev3 - Debian GNU/Linux trixie/sid trixie on X11 - X11 display driver, Multi-window, 1 monitor - OpenGL 3 (Compatibility) - Mesa Intel(R) Graphics (RPL-P) - 13th Gen Intel(R) Core(TM) i7-1360P (16 threads)

**Issue description:** The documentation says that this is a maximum and that the value of -1 means "no limit". However,

- This value is used directly, so setting it to 128 will spawn 128 worker threads regardless of how many cores the user's system has.
- `-1` actually means "default thread count", not "unlimited", and on every platform but web, this is equal to the number of processor cores. On web, this is hard-coded to 1 for reasons unclear to me. (The function that returns the number of processor cores works fine on web and builds that don't support threads don't use this setting or function at all already.)

**URL to the documentation page:** https://docs.godotengine.org/en/latest/classes/class_projectsettings.html#class-projectsettings-property-threading-worker-pool-max-threads