fix: name every reader of a held file out of reach

A release asset absent from the checkout is omitted from the install
list. That omission named only the first core reading it: harm1.wad,
action2.wad and delaweare.wad named gzdoom, so install.py --target
rpi1, where lzdoom runs, kept nothing the builder's list for rpi1
omits. The omission now names the cores of the claims folded onto the
entry too.

scripts/generate_pack.py

@@ -4515,11 +4515,7 @@ def _manifest_core_entries(
             ):
                 systems = _extra_system_ids(fe)
                 record_omission(
-                    full_dest,
-                    fe,
-                    systems[0] if systems else "",
-                    status,
-                    [source_emu] if source_emu else [],
+                    full_dest, fe, systems[0] if systems else "", status, _claim_cores(fe),
                 )
             continue
 
@@ -4554,7 +4550,7 @@ def _manifest_core_entries(
                 systems = _extra_system_ids(fe)
                 record_omission(
                     full_dest, fe, systems[0] if systems else "", "not_found",
-                    [source_emu] if source_emu else [],
+                    _claim_cores(fe),
                 )
             if file_size:
                 pack_only_sizes.append(file_size)
@@ -4668,6 +4664,17 @@ def _manifest_selection(
     ), held
 
 
+def _claim_cores(fe: dict) -> list[str]:
+    """The cores an extra and the claims folded onto it name: an omission
+    names every core reading the file, as a list built for one of them
+    would."""
+    names = {
+        claim.get("source_profile") or claim.get("source_emulator", "")
+        for claim in (fe, *fe.get("other_claims", []))
+    }
+    return sorted(name for name in names if name)
+
+
 def _record_absent(
     absent: list[dict],
     config: dict,