fix: write actual mock port to file for smoke test

.woodpecker/smoke-init.yml

@@ -32,7 +32,10 @@ steps:
     image: python:3-alpine
     commands:
       - apk add --no-cache bash curl jq git coreutils
-      - MOCK_FORGE_PORT=3001 python3 tests/mock-forgejo.py > /tmp/mock.log 2>&1 &
-      # Wait for mock to be ready (might be on a different port if 3001 is in use)
-      - for i in $(seq 1 30); do curl -sf http://localhost:$MOCK_FORGE_PORT/api/v1/version >/dev/null 2>&1 && break || sleep 1; done
-      - SMOKE_FORGE_URL=http://localhost:$MOCK_FORGE_PORT FORGE_URL=http://localhost:$MOCK_FORGE_PORT bash tests/smoke-init.sh
+      - MOCK_FORGE_PORT=3001 MOCK_FORGE_PORT_FILE=/tmp/mock-port python3 tests/mock-forgejo.py > /tmp/mock.log 2>&1 &
+      - MOCK_PID=$!
+      # Wait for mock to be ready
+      - for i in $(seq 1 30); do [ -f /tmp/mock-port ] && break || sleep 1; done
+      - MOCK_PORT=$(cat /tmp/mock-port 2>/dev/null || echo "3001")
+      - for i in $(seq 1 30); do curl -sf http://localhost:$MOCK_PORT/api/v1/version >/dev/null 2>&1 && break || sleep 1; done
+      - SMOKE_FORGE_URL=http://localhost:$MOCK_PORT FORGE_URL=http://localhost:$MOCK_PORT bash tests/smoke-init.sh