Don't require the ROM to exist

Unlike the NRO, we never need to read anything from it. The only downside with this change is it will not be able to check if the ROM path provided actually exists.

The benefit though is you can more easily batch and script ROM paths without needing the Switch's microSD card to be inserted to the PC.

nton/main.py

@@ -43,7 +43,7 @@ def main(version: bool, debug: bool) -> None:
 @click.option("-v", "--version", type=str, default=None, help="Title Version.")
 @click.option("-i", "--icon", type=Path, default=None, help="Title Icon (256x256px recommended, supports any image).")
 @click.option("--id", "id_", type=str, default=None, help="Title ID.")
-@click.option("--rom", type=Path, default=None, help="ROM path for Direct RetroArch Game Forwarding.")
+@click.option("--rom", type=str, default=None, help="ROM path for Direct RetroArch Game Forwarding.")
 def build(
     path: Path,
     name: str | None,
@@ -51,7 +51,7 @@ def build(
     version: str | None,
     icon: Path | None,
     id_: str | None,
-    rom: Path | None
+    rom: str | None
 ) -> int:
     """
     Build an NSP that loads an NRO on the Switch's microSD card.
@@ -65,8 +65,8 @@ def build(
             resolution. A 256x256px image is recommended.
         id_: Set a specific Title ID, otherwise a Random Title ID is used. There's a miniscule chance it could get the
             same Title ID as another installed Title, but it's so miniscule you shouldn't realistically worry about it.
-        rom: Path to a ROM file to create a forwarder that boots directly into the game using RetroArch. The NRO path
-            must be to a RetroArch Core.
+        rom: Path to a ROM file on the Switch's microSD card to create a forwarder that boots directly into the game
+            using RetroArch. The NRO path must be to a RetroArch Core. It must also be an absolute path.
     """
     log = logging.getLogger("build")
     log.info("Building!")
@@ -110,9 +110,8 @@ def build(
             id_ = "01%s000" % os.urandom(6).hex()[:-1]
 
     if rom:
-        if not rom.is_file():
-            log.error(f"The ROM path \"{rom}\" does not exist, or is not a file.")
-            return 1
+        if not rom.startswith("/"):
+            rom = f"/{rom}"
         if not str(path).lower().startswith(f"{path.drive.lower()}:/retroarch/cores/"):
             log.error(f"Setting a ROM path for the forwarder requires the NRO path to be to a RetroArch Core.")
             log.error(f"Make sure you set it to a RetroArch Core and not to RetroArch itself or any other NRO.")
@@ -226,7 +225,7 @@ def build(
 
         next_argv = next_nro_path
         if rom:
-            next_argv += " " + str(rom.resolve().absolute()).replace(f"{rom.drive}:/", "sdmc:/")
+            next_argv += f" sdmc:{rom}"
         next_argv_file.write_text(next_argv)
 
         # only make this directory at this point because we have a high chance of success