Merge remote-tracking branch 'origin/main' into claude/scan-order-compensation

# Conflicts:
#	CHANGELOG.md
#	src/display_manager.py

docs/CONFIG_REFERENCE.md

@@ -128,7 +128,8 @@ Read by `src/vegas_mode/config.py` (`VegasScrollConfig.from_config`). See
 | `min_content_separation` | int, `24` |
 | `min_cut_gap` | int, `6` |
 | `continuous_scroll` | bool, `true` |
-| `smooth_scroll` | bool, `true` |
+| `smooth_scroll` | bool, `true` — move a whole number of pixels per panel refresh, locked to vsync. `scroll_speed` is snapped to the nearest speed the panel can show that way (at 95Hz: 95, 47.5, 31.7 px/s…), measured against the panel's real refresh rate once scrolling starts |
+| `sub_pixel_blend` | bool, `false` — the older smoothing: advance by elapsed time and blend neighbouring pixel columns. Looks anti-aliased in the web preview but shimmers on the panel and is not locked to the refresh. Overrides `smooth_scroll` when on |
 | `extend_threshold_screens` | float, `2.0` |
 | `auto_trim` | bool, `true` |
 | `trim_threshold` | int, `10` |

docs/SCROLL_PERFORMANCE.md

@@ -207,7 +207,10 @@ Fixed by rebuilding the binding: `scripts/build_rgbmatrix_nogil.sh`.
 ### 3. Sub-pixel blending was wrong for this display
 
 Enabling it made things worse, not better — see the rule at the top. It is off
-by default and only Vegas mode opts in via `set_sub_pixel_scrolling(True)`.
+by default everywhere. Vegas mode used to opt in; it now scrolls in whole
+pixels locked to the refresh like the plugin tickers, and keeps the blend only
+behind `display.vegas_scroll.sub_pixel_blend` (default `false`). The blend is
+also why text looked anti-aliased in the web preview while the panel shimmered.
 
 ### 4. Frame-based stepping raced the vsync clock