Initial open-source release

Claude-Session: https://claude.ai/code/session_01B65qLEKnkeYTGdbwhLpjCu

src/platform/commandLine.ts

@@ -0,0 +1,29 @@
+/** Command-line helpers shared by the terminal and External Tools. */
+
+/** Splits a command line (`/bin/zsh --login`, `-c "a b"`) into words, honouring quotes. */
+export function splitCommandLine(line: string): string[] {
+  const out: string[] = [];
+  let cur = "";
+  let quote: string | null = null;
+  let has = false;
+  for (let i = 0; i < line.length; i++) {
+    const c = line[i]!;
+    if (quote) {
+      if (c === quote) quote = null;
+      else if (c === "\\" && quote === '"' && i + 1 < line.length) cur += line[++i];
+      else cur += c;
+    } else if (c === '"' || c === "'") {
+      quote = c;
+      has = true;
+    } else if (c === "\\" && i + 1 < line.length) {
+      cur += line[++i];
+      has = true;
+    } else if (/\s/.test(c)) {
+      if (has || cur) out.push(cur);
+      cur = "";
+      has = false;
+    } else cur += c;
+  }
+  if (has || cur) out.push(cur);
+  return out;
+}