feat: edit working-checkout comparisons with normal editor actions

src/main.rs

@@ -40,10 +40,12 @@ Commands: :w [PATH], :q, :q!, :wq [PATH], :plugins, :PLUGIN [ARGS]
 Buffers: :edit PATH, :buffers, :buffer N, :bnext, :bprev, :bdelete[!] [N]
          :q refuses any dirty buffer; :wq saves active and quits only if all are clean
 Markdown links: :follow_link (primary caret; local files only)
-Diff: :diff (Normal); choose Before then After; Working checkout means disk, not unsaved buffers
-      Tab/Shift+Tab categories/focus; type to search IDs/refs; arrows navigate/scroll; Esc back/close
+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
+      :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-file tree: Ctrl+e hides/shows; A added, M modified, D removed, R renamed (old path shown)
+      Changed files: normal picker/explorer bindings, Ctrl+w close; A/M/D/R status and rename paths
 
 Ruby config: $XDG_CONFIG_HOME/vamp/config.rb or ~/.config/vamp/config.rb
 Set VAMP_RUBY to choose the Ruby executable.