ci: install circuitforge-core before requirements.txt on GitHub CI

Matches snipe's pattern — pip resolves the git+ VCS dep more reliably
when it's pre-installed as a separate step rather than mixed into a
full requirements.txt solve.

.github/workflows/ci.yml

@@ -22,6 +22,9 @@ jobs:
           python-version: '3.12'
           cache: pip
 
+      - name: Install circuitforge-core
+        run: pip install git+https://git.opensourcesolarpunk.com/Circuit-Forge/circuitforge-core.git@main
+
       - name: Install dependencies
         run: pip install -r requirements.txt