feat: log schwab-scraper and mcp-server commit SHAs at container startup

Bake commit SHAs into the Docker image via CI and log them on server
startup so it's easy to verify which version of schwab-scraper is running.

.gitea/workflows/build.yaml

@@ -23,6 +23,8 @@ jobs:
           git clone --depth=1 --branch main \
             "https://x-access-token:${CLONE_TOKEN}@gitea.ext.ben.io/b3nw/schwab-scraper.git" \
             vendor/schwab-scraper
+          cd vendor/schwab-scraper && git rev-parse HEAD > ../schwab-scraper-commit.txt
+          echo "${{ gitea.sha }}" > vendor/mcp-server-commit.txt
 
       - name: Login to Gitea Container Registry
         uses: docker/login-action@v2