feat: Add Docker infrastructure with Caddy and startup scripts (#25, #26)

Issue #25 - Docker multi-service infrastructure:
- Create docker/Dockerfile with multi-stage build, git support, port 8080
- Create docker/docker-compose.yml with app + Caddy services
- Create docker/Caddyfile for HTTPS termination and reverse proxy
- Create docker/.env.example with configuration template

Issue #26 - Startup scripts and tests:
- Create scripts/start.sh for production startup with env validation
- Create scripts/healthcheck.sh for Docker health checks
- Add health endpoint tests to test_mcp_endpoints.py
- Fix middleware order (HealthCheckBypass must wrap BearerAuth)
- Fix pyproject.toml testpaths to use 'tests' directory
- Update test_config.py for new defaults (0.0.0.0:8080)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

scripts/start.sh

@@ -0,0 +1,60 @@
+#!/bin/bash
+# Production startup script for Gitea MCP Remote
+#
+# This script validates the environment and starts the server.
+
+set -e
+
+# Colors for output
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+NC='\033[0m' # No Color
+
+echo -e "${GREEN}Starting Gitea MCP Remote...${NC}"
+
+# Check required environment variables
+check_required_env() {
+    local var_name=$1
+    if [ -z "${!var_name}" ]; then
+        echo -e "${RED}ERROR: Required environment variable $var_name is not set${NC}"
+        return 1
+    fi
+    echo -e "${GREEN}  $var_name is set${NC}"
+}
+
+echo "Checking required environment variables..."
+MISSING=0
+
+check_required_env "GITEA_URL" || MISSING=1
+check_required_env "GITEA_TOKEN" || MISSING=1
+check_required_env "GITEA_OWNER" || MISSING=1
+
+if [ $MISSING -eq 1 ]; then
+    echo -e "${RED}Missing required environment variables. Exiting.${NC}"
+    echo ""
+    echo "Required variables:"
+    echo "  GITEA_URL    - Gitea server URL (e.g., https://gitea.example.com)"
+    echo "  GITEA_TOKEN  - Gitea API token"
+    echo "  GITEA_OWNER  - Default repository owner"
+    echo ""
+    echo "Optional variables:"
+    echo "  GITEA_REPO   - Default repository name"
+    echo "  AUTH_TOKEN   - Bearer token for MCP endpoint authentication"
+    echo "  HTTP_HOST    - Server host (default: 0.0.0.0)"
+    echo "  HTTP_PORT    - Server port (default: 8080)"
+    exit 1
+fi
+
+# Show optional configuration
+echo ""
+echo "Optional configuration:"
+[ -n "$GITEA_REPO" ] && echo -e "  ${GREEN}GITEA_REPO: $GITEA_REPO${NC}" || echo -e "  ${YELLOW}GITEA_REPO: not set (will use per-request)${NC}"
+[ -n "$AUTH_TOKEN" ] && echo -e "  ${GREEN}AUTH_TOKEN: (set)${NC}" || echo -e "  ${YELLOW}AUTH_TOKEN: not set (no auth required)${NC}"
+echo "  HTTP_HOST: ${HTTP_HOST:-0.0.0.0}"
+echo "  HTTP_PORT: ${HTTP_PORT:-8080}"
+
+# Start the server
+echo ""
+echo -e "${GREEN}Starting server...${NC}"
+exec gitea-mcp-remote