feat: better makefile dependency management

Author: gregnr

Makefile

@@ -1,8 +1,8 @@
 WASM_OUT_DIR := wasm
 WASM_OUT_NAME := libpg-query
 WASM_MODULE_NAME := PgQueryModule
-LIBPG_QUERY_REPO := https://github.com/gregnr/libpg_query.git
-LIBPG_QUERY_BRANCH := fix/ar-command-in-makefile
+LIBPG_QUERY_REPO := https://github.com/pganalyze/libpg_query.git
+LIBPG_QUERY_BRANCH := 15-latest
 CACHE_DIR := .cache
 
 OS ?= $(shell uname -s)
@@ -24,7 +24,9 @@ endif
 
 PLATFORM_ARCH := $(PLATFORM)-$(ARCH)
 SRC_FILES := $(wildcard src/*.cc)
-LIBPG_QUERY_DIR := $(CACHE_DIR)/$(PLATFORM_ARCH)/libpg_query
+LIBPG_QUERY_DIR := $(CACHE_DIR)/$(PLATFORM_ARCH)/libpg_query/$(LIBPG_QUERY_BRANCH)
+LIBPG_QUERY_ARCHIVE := $(LIBPG_QUERY_DIR)/libpg_query.a
+LIBPG_QUERY_HEADER := $(LIBPG_QUERY_DIR)/pg_query.h
 CXXFLAGS := -O3
 
 ifdef EMSCRIPTEN
@@ -47,12 +49,19 @@ clean:
 clean-cache:
 	-@ rm -rf $(LIBPG_QUERY_DIR)
 
+# Clone libpg_query source (lives in CACHE_DIR) 
 $(LIBPG_QUERY_DIR):
 	mkdir -p $(CACHE_DIR)
 	git clone -b $(LIBPG_QUERY_BRANCH) --single-branch $(LIBPG_QUERY_REPO) $(LIBPG_QUERY_DIR)
+	
+$(LIBPG_QUERY_HEADER): $(LIBPG_QUERY_DIR)
+
+# Build libpg_query
+$(LIBPG_QUERY_ARCHIVE): $(LIBPG_QUERY_DIR)
 	cd $(LIBPG_QUERY_DIR); $(MAKE) build
 
-$(OUT_FILES): $(LIBPG_QUERY_DIR) $(SRC_FILES)
+# Build libpg-query-node (based on platform)
+$(OUT_FILES): $(LIBPG_QUERY_ARCHIVE) $(LIBPG_QUERY_HEADER) $(SRC_FILES)
 ifdef EMSCRIPTEN
 	@ $(CXX) \
 		$(CXXFLAGS) \