fix: decide hash mismatch by native mode

A declared hash that the local dump contradicts is not one situation. An
existence platform never reads the bytes, so withholding the file lets an
upstream list error remove something the frontend would have loaded; a
hash platform would reject it, so shipping it is pointless.

The mode now decides, at every point that had an opinion: pack building,
core complement, emulator packs, manifests, conformance and
_intentional_hash_exclusion. verify.find_undeclared_files follows, since
verify and generate_pack must agree file for file.

Also here: resolution reports which evidence matched rather than a flat
"exact", a path or filename can no longer override a declared hash, and
safe_extract_zip treats a Windows backslash as the separator it is
instead of refusing the archive.

scripts/verify.py

@@ -370,9 +370,9 @@ def find_undeclared_files(
     relevant = resolve_platform_cores(config, profiles, target_cores=target_cores)
     standalone_set = set(str(c) for c in config.get("standalone_cores", []))
     undeclared = []
-    seen_files: set[tuple[str, str | None]] = set()
+    seen_files: set[tuple] = set()
     # Track archives: archive_name -> {in_repo, emulator, files: [...], ...}
-    archive_entries: dict[str, dict] = {}
+    archive_entries: dict[tuple, dict] = {}
 
     for emu_name, profile in sorted(profiles.items()):
         if profile.get("type") in ("launcher", "alias"):
@@ -391,9 +391,25 @@ def find_undeclared_files(
 
         for f in profile.get("files", []):
             fname = f.get("name", "")
-            # Dedup by (name, archive): a filename declared loose by one core
-            # and inside an archive by another are distinct packaging shapes
-            seen_key = (fname, f.get("archive"))
+            effective_path = (
+                f.get("standalone_path") if is_standalone else f.get("path")
+            ) or fname
+            raw_regions = f.get("region") or []
+            region_key = tuple(
+                str(value) for value in (
+                    raw_regions if isinstance(raw_regions, list) else [raw_regions]
+                )
+            )
+            # Same-name requirements at different paths, for different systems,
+            # or in distinct variant groups are not interchangeable.
+            seen_key = (
+                fname,
+                f.get("archive"),
+                effective_path,
+                f.get("system"),
+                f.get("variant_group"),
+                region_key,
+            )
             if not fname or seen_key in seen_files:
                 continue
             # Skip unsourceable files (documented reason, not a gap)
@@ -436,13 +452,25 @@ def find_undeclared_files(
 
             # Archived files are grouped by archive
             if archive:
-                if archive not in archive_entries:
+                archive_key = (
+                    archive,
+                    f.get("system"),
+                    f.get("variant_group"),
+                    region_key,
+                    is_standalone,
+                )
+                if archive_key not in archive_entries:
                     in_repo = _name_in_index(
                         archive, by_name, by_path_suffix, data_names,
                         by_name_lower,
                     )
-                    archive_entries[archive] = {
+                    archive_entries[archive_key] = {
+                        "profile": emu_name,
                         "emulator": profile.get("emulator", emu_name),
+                        "systems": list(profile.get("systems", [])),
+                        "system": f.get("system"),
+                        "region": f.get("region"),
+                        "variant_group": f.get("variant_group"),
                         "name": archive,
                         "archive": archive,
                         "path": archive,
@@ -457,7 +485,7 @@ def find_undeclared_files(
                         "archive_file_count": 0,
                         "archive_required_count": 0,
                     }
-                entry = archive_entries[archive]
+                entry = archive_entries[archive_key]
                 entry["archive_file_count"] += 1
                 if f.get("required", False):
                     entry["archive_required_count"] += 1
@@ -487,13 +515,22 @@ def find_undeclared_files(
                 if not in_repo:
                     # Hash fallback: the repo may hold the content under a
                     # different filename (exos21.rom vs exos21.bin)
+                    # generate_pack ships a core extra whose local copy
+                    # contradicts the declared hash and reports the divergence.
+                    # verify must agree with the builder or the two reports
+                    # disagree on the same file.
                     _lp, _st = resolve_local_file(f, db, dest_hint=dest)
-                    in_repo = _st not in ("not_found",) and _lp is not None
+                    in_repo = _st != "not_found" and _lp is not None
 
             checks = _parse_validation(f.get("validation"))
             undeclared.append(
                 {
+                    "profile": emu_name,
                     "emulator": profile.get("emulator", emu_name),
+                    "systems": list(profile.get("systems", [])),
+                    "system": f.get("system"),
+                    "region": f.get("region"),
+                    "variant_group": f.get("variant_group"),
                     "name": fname,
                     "path": dest,
                     "required": f.get("required", False),