Address PR review comments

- Refactor targetPaths/findOwnPaths to class-based implementations with
  unified caching and .dir/.rootDir properties alongside resolve methods
- Replace jest.mock with jest.spyOn in plugin-manager.test.ts
- Remove paths compatibility wrapper from repo-tools, migrate all internal
  consumers to use targetPaths from @backstage/cli-common directly
- Fix changeset package name (@techdocs/cli not @backstage/techdocs-cli)
- Add migration examples to cli-common changeset
- Update API report for cli-common

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

packages/create-app/src/createApp.test.ts

@@ -41,6 +41,12 @@ jest.mock('@backstage/cli-common', () => {
     findPaths: jest.fn(),
     findOwnPaths: () => mockOwnPaths,
     targetPaths: {
+      get dir() {
+        return MOCK_TARGET_DIR;
+      },
+      get rootDir() {
+        return '/mock/target-root';
+      },
       resolve: (...paths: string[]) =>
         pathModule.resolve(MOCK_TARGET_DIR, ...paths),
       resolveRoot: (...paths: string[]) =>

packages/create-app/src/createApp.ts

@@ -76,8 +76,8 @@ export default async (opts: OptionValues): Promise<void> => {
   // Use `--path` argument as application directory when specified, otherwise
   // create a directory using `answers.name`
   const appDir = opts.path
-    ? resolvePath(targetPaths.resolve(), opts.path)
-    : resolvePath(targetPaths.resolve(), answers.name);
+    ? resolvePath(targetPaths.dir, opts.path)
+    : resolvePath(targetPaths.dir, answers.name);
 
   Task.log();
   Task.log('Creating the app...');
@@ -100,7 +100,7 @@ export default async (opts: OptionValues): Promise<void> => {
       // Template to temporary location, and then move files
 
       Task.section('Checking if the directory is available');
-      await checkAppExistsTask(targetPaths.resolve(), answers.name);
+      await checkAppExistsTask(targetPaths.dir, answers.name);
 
       Task.section('Creating a temporary app directory');
       const tempDir = await fs.mkdtemp(resolvePath(os.tmpdir(), answers.name));