fix(windows): cross-platform path separators, JSON quoting, and dollar signs

- Add toPosixPath() helper to normalize output paths to forward slashes
- Use string concatenation for relative base paths instead of path.join()
- Apply toPosixPath() to all user-facing file paths in init.cjs output
- Use array-based execFileSync in test helpers to bypass shell quoting
  issues with JSON args and dollar signs on Windows cmd.exe

Fixes 7 test failures on Windows: frontmatter set/merge (3), init
path assertions (2), and state dollar-amount corruption (2).

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

tests/frontmatter-cli.test.cjs

@@ -107,7 +107,7 @@ describe('frontmatter set', () => {
 
   test('handles JSON array value', () => {
     const file = writeTempFile('---\nphase: 01\n---\nbody');
-    const result = runGsdTools(`frontmatter set ${file} --field tags --value '["a","b"]'`);
+    const result = runGsdTools(['frontmatter', 'set', file, '--field', 'tags', '--value', '["a","b"]']);
     assert.ok(result.success, `Command failed: ${result.error}`);
 
     const content = fs.readFileSync(file, 'utf-8');
@@ -140,7 +140,7 @@ describe('frontmatter set', () => {
 describe('frontmatter merge', () => {
   test('merges multiple fields into frontmatter', () => {
     const file = writeTempFile('---\nphase: 01\n---\nbody');
-    const result = runGsdTools(`frontmatter merge ${file} --data '{"plan":"02","type":"tdd"}'`);
+    const result = runGsdTools(['frontmatter', 'merge', file, '--data', '{"plan":"02","type":"tdd"}']);
     assert.ok(result.success, `Command failed: ${result.error}`);
 
     const content = fs.readFileSync(file, 'utf-8');
@@ -153,7 +153,7 @@ describe('frontmatter merge', () => {
 
   test('overwrites existing fields on conflict', () => {
     const file = writeTempFile('---\nphase: 01\ntype: execute\n---\nbody');
-    const result = runGsdTools(`frontmatter merge ${file} --data '{"phase":"02"}'`);
+    const result = runGsdTools(['frontmatter', 'merge', file, '--data', '{"phase":"02"}']);
     assert.ok(result.success, `Command failed: ${result.error}`);
 
     const content = fs.readFileSync(file, 'utf-8');

tests/helpers.cjs

@@ -2,20 +2,35 @@
  * GSD Tools Test Helpers
  */
 
-const { execSync } = require('child_process');
+const { execSync, execFileSync } = require('child_process');
 const fs = require('fs');
 const path = require('path');
 
 const TOOLS_PATH = path.join(__dirname, '..', 'get-shit-done', 'bin', 'gsd-tools.cjs');
 
-// Helper to run gsd-tools command
+/**
+ * Run gsd-tools command.
+ *
+ * @param {string|string[]} args - Command string (shell-interpreted) or array
+ *   of arguments (shell-bypassed via execFileSync, safe for JSON and dollar signs).
+ * @param {string} cwd - Working directory.
+ */
 function runGsdTools(args, cwd = process.cwd()) {
   try {
-    const result = execSync(`node "${TOOLS_PATH}" ${args}`, {
-      cwd,
-      encoding: 'utf-8',
-      stdio: ['pipe', 'pipe', 'pipe'],
-    });
+    let result;
+    if (Array.isArray(args)) {
+      result = execFileSync(process.execPath, [TOOLS_PATH, ...args], {
+        cwd,
+        encoding: 'utf-8',
+        stdio: ['pipe', 'pipe', 'pipe'],
+      });
+    } else {
+      result = execSync(`node "${TOOLS_PATH}" ${args}`, {
+        cwd,
+        encoding: 'utf-8',
+        stdio: ['pipe', 'pipe', 'pipe'],
+      });
+    }
     return { success: true, output: result.trim() };
   } catch (err) {
     return {

tests/state.test.cjs

@@ -205,7 +205,7 @@ None
     );
 
     const result = runGsdTools(
-      "state add-decision --phase 11-01 --summary 'Benchmark prices moved from $0.50 to $2.00 to $5.00' --rationale 'track cost growth'",
+      ['state', 'add-decision', '--phase', '11-01', '--summary', 'Benchmark prices moved from $0.50 to $2.00 to $5.00', '--rationale', 'track cost growth'],
       tmpDir
     );
     assert.ok(result.success, `Command failed: ${result.error}`);
@@ -233,7 +233,7 @@ None
 `
     );
 
-    const result = runGsdTools("state add-blocker --text 'Waiting on vendor quote $1.00 before approval'", tmpDir);
+    const result = runGsdTools(['state', 'add-blocker', '--text', 'Waiting on vendor quote $1.00 before approval'], tmpDir);
     assert.ok(result.success, `Command failed: ${result.error}`);
 
     const state = fs.readFileSync(path.join(tmpDir, '.planning', 'STATE.md'), 'utf-8');