always decompress SHR to completion on launch

fixes https://github.com/a2-4am/4cade/issues/680

src/glue.decompress.a

@@ -6,6 +6,7 @@
 ; Public functions
 ; - DecompressGameHelp
 ; - DecompressSHR
+; - DecompressAuxSHROnIdle
 ; - DecompressAuxSHR
 ; - DecompressDHGR
 ; - DecompressHGR
@@ -49,15 +50,18 @@ DecompressSHR
          bne   DecompressAfterLoad   ; always branches
 
 ;------------------------------------------------------------------------------
-; DecompressAuxSHR
+; DecompressAuxSHR/DecompressAuxSHROnIdle
 ;
 ; in:    compressed SHR data at $1FF8/aux
 ;        file size in sizelo2/sizehi2 as set by ProRWTS2
 ; out:   decompressed SHR data at $2000..$9FFF/aux
 ;        also see notes in DecompressAfterLoad
 ;------------------------------------------------------------------------------
-DecompressAuxSHR
+DecompressAuxSHROnIdle
          bit   SHRRTS                ; V=1 -> allow early exit on keypress
+         !byte $A9
+DecompressAuxSHR
+         clv                         ; V=0 -> always complete decompression
          ldx   #kDecompressInAuxMem  ; data is in auxmem
          ldy   #$A0
          lda   #$1F                  ; target address (hi) -1

src/glue.launch.a

@@ -166,7 +166,7 @@ PlayGameInAY
 @loadLaunchArtwork128K
          lda   gPreloadStatus
          bne   @resumeBackgroundDecompression
-+        jsr   LoadAuxIndexedSHRFile
+         jsr   LoadAuxIndexedSHRFile
          jsr   PreSHRMode
          jsr   DecompressAuxSHR
          jmp   @showLaunchArtwork128K

src/ui.attract.shr.a

@@ -287,7 +287,7 @@ LoadLaunchArtworkInBackground
          lda   #%00000001
          sta   gPreloadStatus
          jsr   PreSHRMode
-         jsr   DecompressAuxSHR
+         jsr   DecompressAuxSHROnIdle
          lda   KBD
          bmi   @turnOffLinearizeAndExit
          lda   #%11111111