fix: mobile terminal scroll via capture-phase touch listeners

- Attach touch listeners to container wrapper in CAPTURE phase so they run
  before xterm.js internals stop propagation
- Add e.stopPropagation() in touchmove after handling scroll to prevent
  xterm.js from conflicting with our scroll
- Add wheel event fallback for mobile browsers that synthesize wheel from touch
- Remove touch-action: none CSS which was blocking native xterm viewport scroll

apps/web/src/styles.css

@@ -3703,7 +3703,6 @@ a.nav-item,
 	padding: 0;
 	overflow: hidden;
 	position: relative;
-	touch-action: none;
 }
 
 /* xterm.js manages its own sizing */