fix(cli): use path.join for remaining cross-platform path issues

Replace string-concatenated paths with path.join in state.ts and
theme-apply.ts for Windows compatibility. Fix exec cwd test to resolve
symlinks (macOS /var -> /private/var).

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

Author: CarlosZiegler

packages/cli/src/lib/__tests__/helpers.exec.test.ts

@@ -1,4 +1,4 @@
-import { mkdtempSync, rmSync } from "node:fs";
+import { mkdtempSync, realpathSync, rmSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
 import { afterEach, describe, expect, it } from "bun:test";
@@ -22,7 +22,9 @@ describe("exec", () => {
   });
 
   it("respects cwd", async () => {
-    const cwd = mkdtempSync(join(tmpdir(), "create-start-kit-dev-"));
+    const cwd = realpathSync(
+      mkdtempSync(join(tmpdir(), "create-start-kit-dev-"))
+    );
     tempDirs.push(cwd);
 
     const result = await exec(

packages/cli/src/lib/state.ts

@@ -1,4 +1,5 @@
 import { existsSync, readFileSync } from "node:fs";
+import { join } from "node:path";
 
 const STATE_FILE = ".setup-state.json";
 
@@ -39,7 +40,7 @@ const DEFAULT_STATE: SetupState = {
 };
 
 function getStatePath(): string {
-  return `${process.cwd()}/${STATE_FILE}`;
+  return join(process.cwd(), STATE_FILE);
 }
 
 export function loadState(): SetupState {

packages/cli/src/theme/theme-apply.ts

@@ -1,4 +1,5 @@
 import { writeFileSync } from "node:fs";
+import { join } from "node:path";
 import { log, spinner } from "@clack/prompts";
 import type {
   BaseColorName,
@@ -82,7 +83,7 @@ export function applyTheme(targetDir: string, config: ThemeConfig): void {
   s.start("Applying theme...");
 
   const css = generateFullAppCss(config);
-  writeFileSync(`${targetDir}/src/app.css`, css, "utf-8");
+  writeFileSync(join(targetDir, "src", "app.css"), css, "utf-8");
 
   s.stop(
     `Theme applied: ${config.theme} (base: ${config.baseColor}, radius: ${config.radius}, font: ${config.font})`