re: the variant reading is refuted; HudResource is the in-game screen config

Censused the 32 bundle-less in-game .prt names with the 68 as control:
4 of 32 appear as an element of some 2D bundle, against 58 of 68.
Being an element is normal for a part that exists; these are not
elements either.  Last iteration's 'not adopted' reading is refuted.
28 names are neither a bundle nor an element.

They are not unreferenced: a HudResource record inside the 2D paks' own
IDXD entries names them -- the in-game screen config, parallel to
tables.pak for menus.  GP_MAIN_GAME_E2D.pak has 6 IDXD entries; two
carry HudResource (24 named fields) beside ArmsStatus, Map, ArmsItem,
RangeFinder, Marker, Manuva, Number; two more carry the
ObjectiveMarker_*/TutorialMarker_* set.

Its values carry subdirectory prefixes -- Hitmark\, Lockon\ -- which my
hand-written prefix list never had.  So I rebuilt the negative the right
way round: harvested every IDXD field value containing a backslash, kept
the 60 commonest directories, and re-swept.  241/376 with the hand list;
241 with hand + harvested -- zero new resolutions.  After the language\
miss, this is the closure that counts: the prefix list came from the
disc, not from me.

Still open: whether the 28 are cut features or assembled at runtime from
sprites.  Nothing static separates those two.

Artefact +45 lines / 0 deletions; the other six regenerate
byte-identical.

docs/re/data/prt-parts.txt

@@ -104,6 +104,51 @@
         pgtarget_laser.prt
         pgtimer.prt
 
+## REFUTED  the bundle-less names are NOT variants declared in a parent bundle
+   in-game names WITHOUT their own bundle (32): appear as an ELEMENT of some 2D bundle: 4
+   CONTROL   in-game names WITH a bundle    (68): appear as an element: 58
+   neither a bundle nor an element -- 28 names:
+        pggauge_armor_eff1.prt
+        pggauge_shield_eff1.prt
+        pghud_GAremainder.prt
+        pghud_OBremainder.prt
+        pghud_arms_active1em.prt
+        pghud_arms_active1oh.prt
+        pghud_arms_active2em.prt
+        pghud_arms_active2oh.prt
+        pghud_arms_active3em.prt
+        pghud_arms_active3oh.prt
+        pghud_range_bar_em.prt
+        pghud_range_main.prt
+        pghud_range_nose.prt
+        pghud_subtarget.prt
+        pghud_target_locator_easy.prt
+        pghud_wing_act_dispersion.prt
+        pghud_wing_alert.prt
+        pghud_wing_damage.prt
+        pgmanuva_eff2.prt
+        pgmanuva_eff3.prt
+        pgmark_em_ob_s.prt
+        pgmsg_update.prt
+        pgremaining.prt
+        pgtarget_G_missile.prt
+        pgtarget_cannon.prt
+        pgtarget_gun.prt
+        pgtarget_laser.prt
+        pgtimer.prt
+
+## CONTROL  a prefix list harvested from the DATA adds nothing
+   directory prefixes taken from IDXD path values: 60
+        jpn\Voice\                     x2699
+        eng\Voice\                     x2382
+        jpn\etc\                       x2220
+        eng\etc\                       x1821
+        Sight\                         x420
+        game:\hidden\                  x348
+        Radar\                         x348
+        Marker\                        x324
+   .prt resolving with the hand list 241 ; with hand+harvested 241 (of 376)
+
 ## `<stem>_sub.rat` sub-bundles inside RATC
    distinct _sub.rat names: 11
         pgmsg_end_sub.rat          in 6 archives  ['GP_MAIN_GAME_D2D.pak', 'GP_MAIN_GAME_E2D.pak']