* feat(core): allow defining global API script on plugin build
Adds `tauri_plugin::Builder::global_api_script_path` so plugin authors can define the JavaScript global API bindings (supposed to be injected to `window.__TAURI__`) at compile time, so the string is only part of the binary when withGlobalTauri is true.
Currently this needs to be done manually at runtime (and it's always added to the binary via include_str).
* prefix variable
* use list of scripts instead of combining them
* static str
* header [skip ci]
* slice
