Merge cli-plugin-api into cli-node

Move createCliPlugin and related types from the standalone
@backstage/cli-plugin-api package into @backstage/cli-node and
remove the now-empty package.

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

packages/cli-internal/package.json

@@ -22,7 +22,7 @@
     "test": "backstage-cli package test"
   },
   "dependencies": {
-    "@backstage/cli-plugin-api": "workspace:^"
+    "@backstage/cli-node": "workspace:^"
   },
   "devDependencies": {
     "@backstage/cli": "workspace:^"

packages/cli-internal/src/InternalCliPlugin.ts

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-import { BackstageCommand, CliPlugin } from '@backstage/cli-plugin-api';
+import { BackstageCommand, CliPlugin } from '@backstage/cli-node';
 import { OpaqueType } from '@internal/opaque';
 
 export const OpaqueCliPlugin = OpaqueType.create<{

packages/cli-internal/src/InternalCommandNode.ts

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-import { BackstageCommand } from '@backstage/cli-plugin-api';
+import { BackstageCommand } from '@backstage/cli-node';
 import { OpaqueType } from '@internal/opaque';
 
 /** @internal */