feat: add counted cc and dd line actions

README.md

@@ -26,6 +26,7 @@ Vamp starts in Normal mode. Press `i`, type text, then Esc to return to Normal.
 | Edit completion snippet arguments | Type to replace the highlighted argument; Tab / Shift+Tab moves next/previous |
 | Save in Normal | Space then `w`, or `:w` then Enter |
 | Undo/redo in Normal | `u` / `U` (Shift+u) |
+| Delete/change whole lines in Normal | `dd` / `cc`; leading counts work (`3dd`, `2cc`) |
 | Search in Normal | `/`, type a literal query, Enter; `n`/`N` for next/previous |
 | Select/copy/cut | `v` characterwise or `V` whole rows, move to extend, then `y`/`d` in Visual |
 | Paste in Normal | `p`/`P` after/before the caret or row for linewise fragments; system clipboard by default |
@@ -45,7 +46,7 @@ Ruby configuration and plugins run with your account's filesystem/process permis
 ## Current limits
 
 - One visible buffer at a time; no splits/tabs or graphical frontend.
-- Modal editing, not full Vim compatibility: characterwise and linewise Visual selections, but no block selection, named registers, or Vim operators. Search is literal, case-sensitive, and single-line.
+- Modal editing, not full Vim compatibility: characterwise and linewise Visual selections and counted `dd`/`cc`, but no block selection, named registers, or general operator–motion grammar. Search is literal, case-sensitive, and single-line.
 - Native opt-in LSP supports diagnostics, go-to-definition, plain-text hover, manual primary-caret completion with snippet arguments, and automatic semantic highlighting—not rename, formatting, or code actions. Completion has no automatic popup or acceptance step; other carets are preserved and translated through the chosen edits. Snippet regex transforms and unresolved variables without defaults are omitted.
 - System clipboard access supports macOS and Linux. Separate clipboard mode keeps internal editing available on unsupported/headless environments.