IcyIsland cutscenes and fixes (#3395)

* fix switch and trampoline death in the crystal mine

* make secret exits and secret paths actually work

* actually fix the paths thingie

* restore intro cutscene

* fix foreground mountain tile

* restore castle cutscene

* restore yeti cutscene

* add a cutscene after defeating the yeti

* fix worldmap yeti hitbox

* various touch-ups and worldmap fixes

* subtitle duration

* add new cutscenes (wip) [ci skip]

* remove old cutscenes
minor fixes in new cutscenes

* modify the crystal mine cutscene to fit with the new castle cutscene

* fix typo [ci skip]

* remove old scripttrigger, add missing full stop [ci skip]

* timing in 'An Unsuspected Follower' [ci skip]

---------

Co-authored-by: Frostwithasideofsalt <[email protected]>

fixes #3390
closes #3394

Author: Narre

data/images/worldmap/common/yeti.sprite

@@ -1,7 +1,7 @@
 (supertux-sprite
   (action
     (name "default")
-    (hitbox 23 90 0 0)
+    (hitbox 23 90 0 64)
 (fps 5)
     (images "../../creatures/yeti/worldmap_1.png"
 "../../creatures/yeti/worldmap_2.png"
@@ -19,7 +19,7 @@
   )
   (action
     (name "solved")
-    (hitbox 0 65 0 0)
+    (hitbox 0 65 0 64)
 (fps 3)
     (images "../../creatures/yeti/iceyeti_dust_wm_0.png"
 "../../creatures/yeti/iceyeti_dust_wm_1.png"