macos: revert pixel-scroll-precision-mode, fix scroll with mwheel

pixel-scroll-precision-mode (from previous commit) breaks scrolling on
NS/Cocoa builds: it rebinds [wheel-up/down] to precision handlers that
do not work with the NS event system, resulting in zero scroll response.

Fix: remove pixel-scroll-precision-mode, use standard mwheel.el:
- require mwheel explicitly (Doom may not load it early enough)
- 3 lines/tick, shift=1, meta=0, ctrl=text-scale
- mouse-wheel-progressive-speed nil (constant speed, no acceleration)
- mouse-wheel-tilt-scroll t (horizontal two-finger scroll)
- explicitly bind [wheel-up/down] to mwheel-scroll (prevents Doom
  remapping from silently eating scroll events)

config.el

@@ -168,35 +168,34 @@ Bound to cmd+v in org-mode and markdown-mode."
         mac-right-option-modifier 'none))
 
 ;; Fix C: Disable mouse clicks in GUI Emacs (prevent accidental cursor movement)
-;; Scroll wheel ([wheel-up/down]) is intentionally NOT disabled — scrolling works.
-;; Mouse movement does not move cursor (mouse-autoselect-window nil above).
+;; Scroll wheel events ([wheel-up/down]) are NOT disabled — scrolling works normally.
+;; Mouse movement does not switch windows (mouse-autoselect-window nil above).
 (when (display-graphic-p)
+  ;; Disable clicks only — NOT wheel events
   (dolist (key '([mouse-1] [mouse-2] [mouse-3]
                  [double-mouse-1] [double-mouse-2] [double-mouse-3]
                  [triple-mouse-1] [triple-mouse-2] [triple-mouse-3]
                  [drag-mouse-1] [drag-mouse-2] [drag-mouse-3]
                  [down-mouse-1] [down-mouse-2] [down-mouse-3]))
     (global-set-key key #'ignore))
-  (setq mouse-highlight nil)
+  (setq mouse-highlight nil))
 
-  ;; Scroll wheel — macOS NS/Cocoa generates pixel-level scroll events from
-  ;; trackpad and Magic Mouse. pixel-scroll-precision-mode (Emacs 29+) handles
-  ;; these natively for smooth, 1:1 scrolling. Line-based mouse-wheel-scroll-amount
-  ;; is kept as fallback for physical scroll wheels that send line events.
-  (setq mouse-wheel-scroll-amount '(3 ((shift) . 1) ((control) . nil))
-        mouse-wheel-progressive-speed nil
-        mouse-wheel-follow-mouse t)
-
-  ;; Enable pixel-precise scrolling (Emacs 29+) — essential for macOS trackpad/
-  ;; Magic Mouse. Translates pixel deltas from NS scroll events into smooth
-  ;; pixel-level buffer scrolling instead of jerky line jumps.
-  (when (fboundp 'pixel-scroll-precision-mode)
-    (pixel-scroll-precision-mode 1)
-    ;; Large scroll threshold: pixel deltas above this trigger line-based scroll
-    ;; (prevents trackpad fling from being interpolated frame-by-frame).
-    (setq pixel-scroll-precision-large-scroll-height 40.0
-          ;; Use momentum scrolling from macOS (trackpad inertia)
-          pixel-scroll-precision-use-momentum t)))
+;; macOS scroll wheel best practice (NS/Cocoa build):
+;; - pixel-scroll-precision-mode is NOT used: it targets X11/Haiku and breaks
+;;   NS/Cocoa scroll event delivery (rebinds [wheel-up/down] to non-working handlers)
+;; - Standard mwheel.el with conservative settings is reliable on macOS
+;; - NS backend converts trackpad + physical wheel to [wheel-up]/[wheel-down] events
+(when (display-graphic-p)
+  (require 'mwheel)
+  ;; 3 lines per scroll tick; shift = 1 line; no progressive acceleration
+  (setq mouse-wheel-scroll-amount    '(3 ((shift) . 1) ((meta) . 0) ((control) . text-scale))
+        mouse-wheel-progressive-speed nil   ; constant speed, no acceleration
+        mouse-wheel-follow-mouse      t     ; scroll window under cursor
+        mouse-wheel-tilt-scroll       t     ; horizontal scroll with tilt/two-finger
+        mouse-wheel-flip-direction    nil)  ; standard direction (not natural)
+  ;; Ensure mwheel-scroll is bound (Doom may remap these)
+  (global-set-key [wheel-up]   #'mwheel-scroll)
+  (global-set-key [wheel-down] #'mwheel-scroll))