feat(KB-221): rename CLI binary from kb to fn

- Rename binary from 'kb' to 'fn' in package.json bin entries
- Update package-config test to expect new binary name 'fn'
- Add changeset to track the binary rename for package consumers

packages/cli/src/__tests__/package-config.test.ts

@@ -19,9 +19,9 @@ function loadWorkflowYaml(name: string): any {
 describe("CLI package.json publishing config", () => {
   const pkg = loadPackageJson("cli");
 
-  it('has "bin" field with kb pointing to ./dist/bin.js', () => {
+  it('has "bin" field with fn pointing to ./dist/bin.js', () => {
     expect(pkg.bin).toBeDefined();
-    expect(pkg.bin.kb).toBe("./dist/bin.js");
+    expect(pkg.bin.fn).toBe("./dist/bin.js");
   });
 
   it('has "files" array with refined globs for dist output', () => {