License the catalog under MIT

COPYRIGHT

@@ -0,0 +1,20 @@
+Promptkit OpenRouter Catalog
+
+Copyright (C) 2026 Eric Rakestraw
+
+SPDX-License-Identifier: MIT
+
+This project's catalog assets, Go code, and documentation are licensed under
+the MIT License. Permission is granted to use, copy, modify, merge, publish,
+distribute, sublicense, and sell copies, subject to the notice requirements
+in the complete license text provided in LICENSE.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+
+Third-party code and assets are subject to their respective license terms.