warp: SELECT opens quick-warp (B1) + relocate intro-skip to PlayIntro

- home/overworld.asm: SELECT in the overworld farcalls WarpMenu, then restarts
  the overworld loop so the fly-warp flags get processed.
- engine/warp_menu.asm (new): WarpMenu reuses the fly-warp machinery
  (wDestinationMap + BIT_FLY_WARP/BIT_USED_FLY). B1 warps to Pallet
  unconditionally to validate the hook; the real destination menu is next.
- Moved the fastboot intro-skip out of home/init.asm into PlayIntro (bank 10)
  to reclaim ~10 bytes of home ROM0 for the overworld hook. Net boot behavior
  is unchanged; new-game path still shows the intro.

5 files changed, 26 insertions, 4 deletions

diff --git a/engine/movie/intro.asm b/engine/movie/intro.asm
index 1381d396..7580063c 100644
--- a/engine/movie/intro.asm
+++ b/engine/movie/intro.asm
@@ -6,6 +6,9 @@
 DEF ANIMATION_END EQU 80
 
 PlayIntro:
+; FASTBOOT: skip the intro entirely if a save file exists
+	farcall CheckForPlayerNameInSRAM
+	ret c
 	xor a
 	ldh [hJoyHeld], a
 	inc a
diff --git a/engine/warp_menu.asm b/engine/warp_menu.asm
new file mode 100644
index 00000000..17cc3904
--- /dev/null
+++ b/engine/warp_menu.asm
@@ -0,0 +1,17 @@
+; Quick-warp menu, opened with SELECT in the overworld (hooked in
+; home/overworld.asm). Reuses the game's fly-warp machinery: set the
+; destination map and the fly-warp flags, then return to the overworld loop,
+; which fades out and warps us in at the destination's fly coordinates.
+
+SECTION "Warp Menu", ROMX
+
+WarpMenu::
+; B1 (pipeline validation): unconditionally warp to Pallet Town.
+	ld a, PALLET_TOWN
+	ld [wDestinationMap], a
+	ld hl, wStatusFlags6
+	set BIT_FLY_WARP, [hl]
+	ASSERT wStatusFlags6 + 1 == wStatusFlags7
+	inc hl
+	set BIT_USED_FLY, [hl]
+	ret
diff --git a/home/init.asm b/home/init.asm
index fc426e29..bef73b7e 100644
--- a/home/init.asm
+++ b/home/init.asm
@@ -98,11 +98,7 @@ Init::
 	dec a
 	ld [wUpdateSpritesEnabled], a
 
-; FASTBOOT: skip the GameFreak/Pikachu intro if a save file exists
-	farcall CheckForPlayerNameInSRAM
-	jr c, .fastbootSkipIntro
 	predef PlayIntro
-.fastbootSkipIntro
 
 	call DisableLCD
 	call ClearVram
diff --git a/home/overworld.asm b/home/overworld.asm
index 4586e5c0..a2626089 100644
--- a/home/overworld.asm
+++ b/home/overworld.asm
@@ -73,6 +73,11 @@ OverworldLoopLessDelay::
 .notSimulating
 	ldh a, [hJoyPressed]
 .checkIfStartIsPressed
+	bit B_PAD_SELECT, a       ; WARP MENU hotkey
+	jr z, .notWarpHotkey
+	farcall WarpMenu
+	jp OverworldLoop
+.notWarpHotkey
 	bit B_PAD_START, a
 	jr z, .startButtonNotPressed
 ; if START is pressed
diff --git a/main.asm b/main.asm
index 99860198..fb970f95 100644
--- a/main.asm
+++ b/main.asm
@@ -424,3 +424,4 @@ INCLUDE "engine/pikachu/pikachu_emotions.asm"
 INCLUDE "engine/pikachu/pikachu_movement.asm"
 INCLUDE "engine/pikachu/pikachu_pic_animation.asm"
 INCLUDE "engine/debug/debug_menu.asm"
+INCLUDE "engine/warp_menu.asm"