docs: address review feedback on comments

Per @vicb's review:
- helpers.ts: rewrite quoteShellMeta docstring so it describes both the
  Windows and POSIX branches with equal weight, rather than treating
  POSIX as a footnote. The function works on both platforms.
- helpers.ts: simplify the inner POSIX comment to "POSIX shell quoting"
  per the suggestion.
- run-wrangler.ts: hoist the shell:false / DEP0190 explanation to the
  top-level comment block so it covers both branches, then describe
  the POSIX path and the Windows path in turn. Drop the now-redundant
  inner comment in the POSIX spawn call.
- run-wrangler.ts: restore the stdio explanatory comment that was lost
  when stdio was hoisted to a const in an earlier refactor.

No behavioral changes.

packages/cloudflare/src/cli/commands/utils/helpers.ts

@@ -73,32 +73,32 @@ export async function getEnvFromPlatformProxy(options: GetPlatformProxyOptions,
 }
 
 /**
- * Escape a single argument so it survives the `cmd.exe /d /s /c "<command line>"` invocation
- * used by `runWrangler` on Windows (paired with `windowsVerbatimArguments: true`).
+ * Escape a single argument for shell-style invocation. Cross-platform.
  *
- * The algorithm matches `cross-spawn`'s `escapeArgument`:
+ * On Windows, `runWrangler` invokes `cmd.exe /d /s /c "<command line>"` with
+ * `windowsVerbatimArguments: true`. The algorithm matches `cross-spawn`'s `escapeArgument`:
  *   1. Wrap the value in `"..."`, doubling backslash sequences that precede a quote per the
  *      Windows command-line argument rules.
  *   2. Caret-escape every cmd.exe metacharacter, including the wrapping quotes themselves.
+ * The wrapping carets are needed for the OUTER `cmd /c "..."` parse: cmd.exe consumes them
+ * and the receiving program sees a normally-quoted argument. Crucially, `^` must NOT be
+ * applied inside an un-caret-escaped quoted region, because cmd.exe treats `^` as literal
+ * inside double quotes (this was the bug an earlier shell-quote-style implementation hit).
  *
- * The carets are needed for the OUTER `cmd /c "..."` parse (where the inner quotes would
- * otherwise terminate the command-line string); cmd.exe consumes them and the receiving
- * program sees a normally-quoted argument. Crucially, `^` must NOT be applied inside an
- * un-caret-escaped quoted region: `cmd.exe` treats `^` as literal inside double quotes,
- * which is the bug an earlier shell-quote-style implementation suffered from.
+ * On POSIX, the value is quoted using standard POSIX shell rules (single quotes by default,
+ * double quotes when the value contains a single quote, backslash-escapes for bare values).
+ * `runWrangler` itself does not invoke a shell on POSIX, but this branch is preserved so the
+ * function behaves usefully for any direct caller.
  *
- * Not used on POSIX, where `runWrangler` spawns the package manager directly with
- * `shell: false` and each argv entry is passed verbatim.
- *
- * Reference: https://github.com/moxystudio/node-cross-spawn/blob/master/lib/util/escape.js
- *            https://qntm.org/cmd
+ * References: https://github.com/moxystudio/node-cross-spawn/blob/master/lib/util/escape.js
+ *             https://qntm.org/cmd
  *
  * @param arg
- * @returns escaped arg suitable for embedding in a `cmd /c "..."` command line
+ * @returns escaped arg
  */
 export function quoteShellMeta(arg: string) {
 	if (process.platform !== "win32") {
-		// POSIX fallback (preserved for any external callers): standard shell quoting.
+		// POSIX shell quoting.
 		if (/["\s]/.test(arg) && !/'/.test(arg)) {
 			return `'${arg.replace(/(['\\])/g, "\\$1")}'`;
 		}

packages/cloudflare/src/cli/commands/utils/run-wrangler.ts

@@ -112,6 +112,9 @@ export function runWrangler(
 		]),
 	];
 
+	// Always pipe stderr so that we can capture it for inspection.
+	// Keep stdin and stdout as "inherit" when not piping logs to maintain TTY detection
+	// (wrangler checks `process.stdin.isTTY && process.stdout.isTTY` for interactive mode).
 	const stdio: ("inherit" | "ignore" | "pipe")[] =
 		shouldPipeLogs || noLogs ? ["ignore", "pipe", "pipe"] : ["inherit", "inherit", "pipe"];
 
@@ -124,16 +127,18 @@ export function runWrangler(
 		CLOUDFLARE_LOAD_DEV_VARS_FROM_DOT_ENV: "false",
 	};
 
-	// On Windows the package manager binary is typically a `.cmd` shim. Per Node.js docs
-	// https://nodejs.org/api/child_process.html#spawning-bat-and-cmd-files-on-windows the
-	// recommended way to invoke a `.cmd`/`.bat` is to spawn `cmd.exe` directly with `/c`,
-	// rather than relying on `shell: true` (which emits DEP0190 and would re-tokenize values).
-	// We pre-escape every token with `quoteShellMeta` and pass the joined command line as a
-	// single quoted string with `windowsVerbatimArguments: true` so Node does not re-escape it.
-	// This mirrors how `cross-spawn` handles non-`.exe` commands on Windows.
+	// We use `shell: false` everywhere to avoid DEP0190.
+	// See https://nodejs.org/api/deprecations.html#dep0190-passing-args-to-nodechild-process-execfilespawn-with-shell-option
 	//
-	// On POSIX we spawn the package manager directly with `shell: false`, which avoids DEP0190
-	// and lets each value be passed verbatim as its own argv entry.
+	// On POSIX we can spawn the package manager binary directly: each value is passed verbatim
+	// as its own argv entry.
+	//
+	// On Windows the package manager is typically a `.cmd` shim. Per Node.js docs
+	// (https://nodejs.org/api/child_process.html#spawning-bat-and-cmd-files-on-windows) the
+	// recommended way to invoke a `.cmd`/`.bat` without `shell: true` is to spawn `cmd.exe`
+	// directly with `/c`. We pre-escape every token with `quoteShellMeta` and pass the joined
+	// command line as a single quoted string with `windowsVerbatimArguments: true` so Node
+	// does not re-escape it. This mirrors how `cross-spawn` handles non-`.exe` commands.
 	const result = isWin
 		? spawnSync(
 				"cmd.exe",
@@ -151,8 +156,6 @@ export function runWrangler(
 				}
 			)
 		: spawnSync(options.packager, packagerArgs, {
-				// Setting `shell` to `false` to avoid DEP0190.
-				// See https://nodejs.org/api/deprecations.html#dep0190-passing-args-to-nodechild-process-execfilespawn-with-shell-option
 				shell: false,
 				stdio,
 				env,