feat(infra): add Forgejo runner registration script

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

scripts/mac-mini/setup-forgejo-runner.sh

@@ -0,0 +1,49 @@
+#!/bin/bash
+# Register Forgejo Runner on Mac Mini
+# Run after Forgejo is up and admin user exists
+set -e
+
+DOCKER="${DOCKER_CMD:-/usr/local/bin/docker}"
+FORGEJO_URL="http://localhost:3041"
+FORGEJO_PUBLIC_URL="https://git.mana.how"
+
+# Step 1: Get runner registration token from Forgejo API
+echo "=== Getting runner registration token ==="
+API_TOKEN=$(cat /Volumes/ManaData/forgejo-api-token 2>/dev/null || echo "")
+if [ -z "$API_TOKEN" ]; then
+    echo "No API token found. Generate one:"
+    echo "  $DOCKER exec --user git mana-core-forgejo forgejo admin user generate-access-token --username till --token-name runner-setup --scopes all"
+    echo "  Save to: /Volumes/ManaData/forgejo-api-token"
+    exit 1
+fi
+
+RUNNER_TOKEN=$(curl -s -X POST "$FORGEJO_URL/api/v1/user/actions/runners/registration-token" \
+    -H "Authorization: token $API_TOKEN" | python3 -c "import sys,json; print(json.load(sys.stdin)['token'])")
+
+echo "Runner token: $RUNNER_TOKEN"
+
+# Step 2: Start runner container
+echo ""
+echo "=== Starting Forgejo Runner ==="
+$DOCKER compose -f docker-compose.macmini.yml up -d forgejo-runner
+
+# Step 3: Register runner
+echo ""
+echo "=== Registering runner ==="
+sleep 5
+
+$DOCKER exec mana-core-forgejo-runner forgejo-runner register \
+    --instance "$FORGEJO_PUBLIC_URL" \
+    --token "$RUNNER_TOKEN" \
+    --name "mac-mini" \
+    --labels "ubuntu-latest:docker://node:20,go:docker://golang:1.25-alpine,docker:docker://docker:dind" \
+    --no-interactive
+
+# Step 4: Start runner daemon
+echo ""
+echo "=== Starting runner daemon ==="
+$DOCKER restart mana-core-forgejo-runner
+
+echo ""
+echo "=== Runner registered and started ==="
+echo "Check status: $FORGEJO_PUBLIC_URL/-/admin/runners"