fix: source-verified corrections on 7 profiles

beetle_pce: +core_classification, +upstream, cores=[mednafen_pce],
alt_names→aliases. 6 files confirmed loaded by code.
mame: removed 19 phantom XaviX entries (MACHINE_IS_BIOS_ROOT commented
out in source). 80 real BIOS sets verified.
mame2010: fixed galgbios.zip source_ref, documented cheat.zip as
non-functional in libretro port (cheatpath never initialized).
ishiiruka: trimmed verbose advisory notes to factual descriptions.
mamearcade: added system: field to 29 bios_zip entries, 24 new systems.
mednafen_ngp: removed redundant cores: on alias, added note:.
mednafen_gba: normalized validation format to flow sequence.

emulators/mame2010.yml

@@ -47,8 +47,9 @@ notes: |
 
   hiscore.dat is embedded in binary (precompile/hiscore_dat.h). External
   hiscore.dat loadable via core option mame-external_hiscore from
-  system_dir/mame2010/. Cheats use per-game XML files (cheat.zip in
-  metadata/). Samples in system_dir/mame2010/samples/.
+  system_dir/mame2010/. cheatpath declared but never initialized in
+  libretro port (cheat loading non-functional). Samples in
+  system_dir/mame2010/samples/.
 
   ROM naming follows MAME 0.139 conventions.
 
@@ -64,7 +65,7 @@ files:
     required: false
     category: game_data
     source_ref: "src/emu/cheat.c:1027"
-    note: "per-game XML cheat files in ZIP, loaded from system_dir/mame2010/"
+    note: "per-game XML cheat files in ZIP, cheatpath never initialized in libretro port (non-functional)"
 
   # SNK Neo Geo MVS/AES
   - name: neogeo.zip
@@ -403,7 +404,7 @@ files:
   - name: galgbios.zip
     required: true
     category: bios_zip
-    source_ref: "src/mame/drivers/galaxia.c"
+    source_ref: "src/mame/drivers/tmaster.c"
 
   - name: gq863.zip
     required: true