fix: skip omitted diff lines instead of expanding excerpts during navigation

src/main.rs

@@ -44,7 +44,8 @@ Buffers: :edit PATH, :buffers, :buffer N, :buffer_next, :buffer_previous, :buffe
 Markdown links: :follow_link (primary caret; local files only)
 Diff: :diff (Normal); choose Before then After; Working checkout After edits live unsaved buffers
       Before and historical/remote After stay read-only; Tab/Shift+Tab categories/Normal focus
-      Type to search IDs/refs; Normal [/] expands excerpts; Insert brackets remain literal text
+      Type to search IDs/refs; navigation skips omitted lines without expanding excerpts
+      Normal [/] explicitly expands context; Insert brackets remain literal text
       :diff.close exits explicitly; Esc cancels modes/prompts/filtering without closing the diff
       Remote refs/history load into temporary comparison repos without changing active refs/checkout
       Changed files: normal picker/explorer bindings, Ctrl+w close; A/M/D/R status and rename paths