refactor(makefile): auto-detect container runtime, remove systemd workarounds

Replace hardcoded 'podman' with auto-detected CONTAINER_RUNTIME variable
that prefers docker and falls back to podman. Override with:
  CONTAINER_RUNTIME=podman make rebuild-app

Remove the ensure_healthy and compose_up macros that worked around
podman-compose hanging on non-systemd systems (e.g., Void Linux with
runt). These are no longer needed — healthchecks are now handled by
plain wait loops in the targets themselves, and compose up -d no longer
blocks on health conditions.

Makefile

@@ -7,47 +7,9 @@ ifneq (,$(wildcard ./.env))
     export
 endif
 
-# On non-systemd systems (e.g., Void Linux with runit), podman healthchecks are
+# Auto-detect container runtime: prefer docker, fall back to podman
-# never triggered automatically because podman relies on systemd timers.
+# Override with: CONTAINER_RUNTIME=podman make rebuild-app
-# Additionally, podman-compose up -d blocks forever waiting for service_healthy
+CONTAINER_RUNTIME ?= $(shell command -v docker 2>/dev/null || command -v podman 2>/dev/null)
-# conditions that never resolve. This macro:
-#   1. Waits for the DB to accept connections, triggers its healthcheck
-#   2. Starts the app container, waits for it, triggers its healthcheck
-# On systemd systems, the runtime check skips everything.
-# See: https://github.com/containers/podman/pull/27033
-define ensure_healthy
-	@if [ ! -d /run/systemd/system ]; then \
-		echo "Non-systemd: waiting for database..."; \
-		i=0; \
-		until podman exec bookhoard_db pg_isready -U postgres >/dev/null 2>&1; do \
-			i=$$((i+1)); if [ $$i -gt 30 ]; then echo "  Database failed to start"; exit 1; fi; \
-			sleep 2; \
-		done; \
-		podman healthcheck run bookhoard_db >/dev/null 2>&1 || true; \
-		podman start bookhoard 2>/dev/null || true; \
-		echo "Non-systemd: waiting for application..."; \
-		i=0; \
-		until podman exec bookhoard curl -sf http://localhost:8765/health >/dev/null 2>&1; do \
-			i=$$((i+1)); if [ $$i -gt 30 ]; then echo "  Application failed to start"; exit 1; fi; \
-			sleep 2; \
-		done; \
-		podman healthcheck run bookhoard >/dev/null 2>&1 || true; \
-		echo "  Services healthy"; \
-	fi
-endef
-
-# podman-compose up -d blocks forever on non-systemd waiting for service_healthy.
-# This macro runs compose with a timeout on non-systemd to let it create containers
-# without hanging. Pass compose flags via the COMPOSE_UP_ARGS variable.
-# Usage: $(call compose_up,--build --force-recreate)
-# On systemd systems, the timeout is skipped.
-define compose_up
-	@if [ -d /run/systemd/system ]; then \
-		podman compose up $1 -d; \
-	else \
-		timeout 15 podman compose up $1 -d || true; \
-	fi
-endef
 
 # Default target
 help:
@@ -86,24 +48,23 @@ test:
 # Run integration tests in containers (matches production environment)
 test-integration:
 	@echo "Building test containers..."
-	podman compose --profile tests build
+	$(CONTAINER_RUNTIME) compose --profile tests build
 	@echo "Starting application containers..."
-	$(call compose_up,db app)
+	$(CONTAINER_RUNTIME) compose up -d db app
-	$(ensure_healthy)
 	@echo "Waiting for services to be healthy..."
-	@until podman exec bookhoard_db pg_isready -U postgres > /dev/null 2>&1; do \
+	@until $(CONTAINER_RUNTIME) exec bookhoard_db pg_isready -U postgres > /dev/null 2>&1; do \
 		echo "  Database not ready yet..."; \
 		sleep 2; \
 	done; \
 	echo "  ✓ Database is ready"
-	@until podman exec bookhoard curl -sf http://localhost:8765/health > /dev/null 2>&1; do \
+	@until $(CONTAINER_RUNTIME) exec bookhoard curl -sf http://localhost:8765/health > /dev/null 2>&1; do \
 		echo "  Application not ready yet..."; \
 		sleep 2; \
 	done; \
 	echo "  ✓ Application is ready"
 	@echo ""
 	@echo "Running integration tests in container..."
-	podman compose --profile tests run --rm tests
+	$(CONTAINER_RUNTIME) compose --profile tests run --rm tests
 	@echo ""
 	@echo "✅ Integration tests completed!"
 	@echo "📝 Containers are still running. Use 'make logs' to view logs or 'make clean' to stop."
@@ -114,87 +75,76 @@ test-all: test test-integration
 # Rebuild app container only (preserve DB, with cache)
 rebuild-app:
 	@echo "Rebuilding app container (database stays running)..."
-	$(call compose_up,--build --force-recreate app)
+	$(CONTAINER_RUNTIME) compose up --build --force-recreate -d app
-	$(ensure_healthy)
 	@echo "✓ App container rebuilt and restarted"
 
 # Rebuild app container only (preserve DB, no cache)
 rebuild-app-force:
 	@echo "Force rebuilding app container (database stays running, no cache)..."
-	podman compose build --no-cache app
+	$(CONTAINER_RUNTIME) compose build --no-cache app
-	$(call compose_up,--force-recreate app)
+	$(CONTAINER_RUNTIME) compose up --force-recreate -d app
-	$(ensure_healthy)
 	@echo "✓ App container rebuilt and restarted"
 
 # Rebuild all containers (preserve DB, with cache)
 rebuild:
 	@echo "Rebuilding all containers (database preserved)..."
-	$(call compose_up,--build --force-recreate)
+	$(CONTAINER_RUNTIME) compose up --build --force-recreate -d
-	$(ensure_healthy)
 	@echo "✓ All containers rebuilt and restarted"
 
 # Rebuild all containers (preserve DB, no cache)
 rebuild-force:
 	@echo "Force rebuilding all containers (database preserved, no cache)..."
-	podman compose build --no-cache
+	$(CONTAINER_RUNTIME) compose build --no-cache
-	$(call compose_up,--force-recreate)
+	$(CONTAINER_RUNTIME) compose up --force-recreate -d
-	$(ensure_healthy)
 	@echo "✓ All containers rebuilt and restarted"
 
 # Rebuild all containers (remove DB, no cache)
 rebuild-force-db:
 	@echo "Force rebuilding all containers (database will be DELETED, no cache)..."
-	podman compose down -v
+	$(CONTAINER_RUNTIME) compose down -v
-	podman compose build --no-cache
+	$(CONTAINER_RUNTIME) compose build --no-cache
-	$(call compose_up,--force-recreate)
+	$(CONTAINER_RUNTIME) compose up --force-recreate -d
-	$(ensure_healthy)
 	@echo "✓ All containers rebuilt and restarted"
 
 # Stop and remove containers
 clean:
-	podman compose down -v
+	$(CONTAINER_RUNTIME) compose down -v
 
 # Quick start (if already built)
 up:
-	$(compose_up)
+	$(CONTAINER_RUNTIME) compose up -d
-	$(ensure_healthy)
 
 # Stop all containers (alias for clean)
 down:
-	podman compose down
+	$(CONTAINER_RUNTIME) compose down
 
 # Restart app container (preserves database)
 restart:
 	@echo "Restarting app container (database stays running)..."
-	podman compose restart app
+	$(CONTAINER_RUNTIME) compose restart app
 	@echo "✓ App container restarted"
 
 # Show container status
 ps:
-	podman compose ps
+	$(CONTAINER_RUNTIME) compose ps
 
 # Show container logs
 logs:
-	podman compose logs -f
+	$(CONTAINER_RUNTIME) compose logs -f
 
 # Start containers with test mode enabled for manual testing
 test-env-up:
 	@echo "Starting containers with test mode enabled..."
-	@if [ -d /run/systemd/system ]; then \
+	TEST_MODE=true RATE_LIMIT_ENABLED=false REQUESTS_PER_MINUTE=1000 $(CONTAINER_RUNTIME) compose up --build --force-recreate -d
-		TEST_MODE=true RATE_LIMIT_ENABLED=false REQUESTS_PER_MINUTE=1000 podman compose up --build --force-recreate -d; \
-	else \
-		TEST_MODE=true RATE_LIMIT_ENABLED=false REQUESTS_PER_MINUTE=1000 timeout 15 podman compose up --build --force-recreate -d || true; \
-	fi
-	$(ensure_healthy)
 	@echo "Waiting for services to be ready..."
-	@until podman exec bookhoard_db pg_isready -U postgres > /dev/null 2>&1; do sleep 1; done
+	@until $(CONTAINER_RUNTIME) exec bookhoard_db pg_isready -U postgres > /dev/null 2>&1; do sleep 1; done
-	@until podman exec bookhoard curl -sf http://localhost:8765/health > /dev/null 2>&1; do sleep 1; done
+	@until $(CONTAINER_RUNTIME) exec bookhoard curl -sf http://localhost:8765/health > /dev/null 2>&1; do sleep 1; done
 	@echo "✓ Test environment is ready!"
 	@echo "Application available at http://localhost:8765"
 
 # Stop test environment
 test-env-down:
-	podman compose down -v
+	$(CONTAINER_RUNTIME) compose down -v
 
 # Verify project guidelines compliance
 verify-guidelines: