feat: packs leave out what the emulator installs

A file or tree installed with the emulator is already on the user's machine, so packs, install manifests and verify's pack count leave it out. bundled is scoped by mode like any entry: Dolphin's Sys and PPSSPP's assets ship with the standalone releases, not with the libretro cores, so they now follow the libretro build only and still reach RetroArch packs. PrimeHack, standalone only, ships its own Sys.

scripts/packextras.py

@@ -875,6 +875,11 @@ def _collect_emulator_extras(
         for destination in seen:
             taken[destination] = baseline_claims.setdefault(destination, {})
     for u in undeclared:
+        if u.get("bundled"):
+            # Installed with the emulator for this build: already on the
+            # user's machine. The mode a file is bundled for was settled
+            # upstream, an entry scoped to another build never gets here.
+            continue
         if not u["in_repo"] and absent is None:
             continue
         # For archive entries, use the archive name for resolution