fix(terminal): lower scroll sensitivity to 2 after testing

4 lines per wheel notch overshoots badly on a normal mouse; 2 is a
comfortable middle between xterm's default of 1 and the 3-5 range
requested in #254. Wheel resolution varies enough between devices that
a tunable setting is the real fix - #254 stays open for that.

Author: johannesjo

src/lib/terminalConstants.ts

@@ -5,7 +5,7 @@
 // xterm's fastScrollSensitivity default of 5, so we leave that one alone.
 export const TERMINAL_SCROLL_OPTIONS = {
   scrollback: 10_000,
-  scrollSensitivity: 4,
+  scrollSensitivity: 2,
 } as const;
 
 // Pre-computed base64 lookup table — avoids atob() intermediate string allocation.