re: who selects a loadout -- the pak entry does; the Arsenal pak is stage-scoped

Settled by elimination with two controls.  The 15 loadout names appear
as a field VALUE nowhere on the disc -- 0 occurrences across every pak
-- while the control Arbalest_155KG, which is referenced, appears 150
times as a value in the same pak.  They occur only as the field names of
the UNITS record.  They are not in the executable either; control:
WEAPONS (a section key) is, Arbalest_155KG is not.

So nothing references a loadout by name.  The selection is which pak
entry the Hangar loads.  GP_HANGAR_ARSENAL.pak has 180 IDXD entries in
10 shapes; 168 carry a UNITS roster = 28 stages x 6 languages, and the
other 12 = 2 x 6.  Each entry is one stage's whole Hangar config, and
its UNITS roster is the flight for that stage -- 5 distinct rosters over
15 / 5 / 5 / 2 / 1 stages, including one where Rhino2-Katana flies
alone.  Every count is a multiple of 6 and they sum to 28, the disc's
stage count by a fourth independent route.

Corrects the previous commit: it read the pak with setdefault, so
'15 loadouts / 24 allow-lists / STANDARD_ARM1 has 11 entries' is the
union of first-seen records, not one table.  Contents vary per entry --
PlayerSET_ARM1 has 5 distinct contents, STANDARD_ARM1 3, ExSET_NOSE 4.
The chain and both controls (60/60, 70/88) are per-record and
unaffected; only the per-list sizes were over-generalised.

Not settled: the entry filenames.  name_hash probing over 8 templates x
40 indices x 6 languages resolved 0, while the same probe's controls
<lang>\weapon.tbl and <lang>\strings.tbl resolved 12/12.

Artefact +40 lines / 1 changed heading; the other four regenerate
byte-identical.

tools/re-capture/hangar_loadouts.py

@@ -43,12 +43,40 @@ def main():
             elif set(SLOTS) <= set(n): loadouts.setdefault(nm, r)
             elif set(n) == {'Type'}: allow.setdefault(nm, r)
 
+    idxd = [(h, U.parse(b)) for h, b in pak_entries(ars) if b[:4] == b'IDXD']
+    withu = [(h, r) for h, r in idxd if any(x['squadron'] == 'UNITS' for x in r)]
+    rosters = collections.Counter()
+    for h, recs in withu:
+        for r in recs:
+            if r['squadron'] == 'UNITS':
+                rosters[tuple(sorted(n for t, n, v in r['fields']))] += 1
+
     print("# The Hangar loadout system")
     print("# Regenerate: python3 tools/re-capture/hangar_loadouts.py")
     print("# See docs/re/structures/hangar-loadout-system.md")
-    print("\n## counts")
+    print("\n## the pak is STAGE-SCOPED -- one config entry per stage per language")
+    print("   total pak entries %4d   IDXD entries %3d" % (len(pak_entries(ars)), len(idxd)))
+    print("   entries carrying a UNITS roster %3d  = %d stages x 6 languages"
+          % (len(withu), len(withu) // 6))
+    print("   entries without one              %3d  = %d x 6 (the item table + siblings)"
+          % (len(idxd) - len(withu), (len(idxd) - len(withu)) // 6))
+    print("   every roster count is a multiple of 6: %s ; they sum to %d stages"
+          % (all(c % 6 == 0 for c in rosters.values()), sum(c // 6 for c in rosters.values())))
+    print("\n## the %d distinct UNITS rosters -- who is in the flight, per stage" % len(rosters))
+    for t, c in rosters.most_common():
+        print("   %2d stage(s)  %d pilots: %s" % (c // 6, len(t), ", ".join(t)))
+
+    print("\n## counts, UNION over all entries (each name first-seen)")
     print("   arsenal items %3d   loadout records %3d   per-slot allow-lists %3d"
           % (len(items), len(loadouts), len(allow)))
+    var = collections.defaultdict(set)
+    for h, recs in idxd:
+        for r in recs:
+            if set(U.named(r)) == {'Type'}:
+                var[r['squadron']].add(tuple(v for t, n, v in r['fields'] if n is None))
+    print("\n## allow-list CONTENT VARIES BY ENTRY -- distinct contents per name")
+    for k in sorted(var):
+        print("   %-18s %d" % (k, len(var[k])))
 
     print("\n## loadout records")
     for nm in sorted(loadouts):