ui: editor QoL — line ops, auto-close, goto, smart home, Ctrl+D

Line operations:
- Alt+↑/↓   — move current line up / down (swaps with adjacent line)
- Alt+Shift+↓/↑ — duplicate line below / above
- Ctrl+Shift+K  — delete current line
- Ctrl+L        — select entire current line (including newline)

Auto-close brackets and quotes:
- ( [ { " ' ` — inserts matching close, cursor placed inside
- Wrap selection — if text is selected, typing an opener wraps it
- Skip-over — typing a close char when it's already next → jumps past it
- Smart backspace — deletes BOTH chars when cursor sits between a matched pair
- Guards: skip ' auto-close after word chars (contractions); skip auto-close
  when next char is a word char (prevents disrupting existing text)

Navigation:
- Ctrl+G — Go to Line bar (pre-filled with current line, shows "of N")
- Smart Home — first press → first non-whitespace; second → col 0
- Ctrl+D — first press: select word at cursor; subsequent: cycle through
  all occurrences (wraps around), integrates with word highlight overlay

Keyboard shortcuts panel:
- Added "Editor Keyboard Shortcuts" section to the How do I use this panel

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Plugin/unraid/css/varaverk.css

@@ -394,6 +394,16 @@
 .vv-es-sel  { color: #555; }
 .vv-es-lang { margin-left: auto; color: #4a6a7a; }
 
+/* Go to line bar */
+#vv-goto-bar { display: none; align-items: center; gap: 8px; padding: 5px 8px;
+               margin-bottom: 5px; background: #161616; border: 1px solid #333;
+               border-radius: 4px; font-size: 12px; }
+#vv-goto-bar.vv-goto-open { display: flex; }
+#vv-goto-input { width: 68px; background: #0d0d0d; border: 1px solid #333; color: #ddd;
+                 padding: 4px 8px; border-radius: 3px; font-family: monospace; font-size: 12px; }
+#vv-goto-input:focus { border-color: #6495ed; outline: none; }
+.vv-goto-info { font-size: 11px; color: #555; white-space: nowrap; flex-shrink: 0; }
+
 /* Undo / Redo buttons */
 .vv-undo-redo-btn { border-color: #444 !important; color: #666 !important; }
 .vv-undo-redo-btn:not([disabled]):hover { border-color: #777 !important; color: #ccc !important; background: #1e1e1e !important; }