feat: introduce WeKnora Lite edition with lightweight configuration and deployment

- Added a new `.env.lite.example` file for the Lite version, providing a minimal configuration template.
- Updated `.env.example` to remove deprecated variables and include new Docreader settings.
- Enhanced Docker configurations to support the Lite version, including a new Dockerfile for the Docreader service.
- Introduced a Makefile target for building and running the Lite version, along with packaging capabilities.
- Created GitHub workflows for building and releasing Lite binaries, including Homebrew formula support.
- Implemented a new service file for managing the Lite version as a system service.

This update enables a streamlined, single-binary deployment of WeKnora, reducing external dependencies and simplifying setup.

docreader/scripts/generate_proto.sh

@@ -1,5 +1,5 @@
 #!/bin/bash
-set -x
+set -ex
 
 # 设置目录
 PROTO_DIR="docreader/proto"
@@ -13,12 +13,16 @@ python3 -m grpc_tools.protoc -I${PROTO_DIR} \
     --grpc_python_out=${PYTHON_OUT} \
     ${PROTO_DIR}/docreader.proto
 
-# 生成Go代码
-protoc -I${PROTO_DIR} --go_out=${GO_OUT} \
-    --go_opt=paths=source_relative \
-    --go-grpc_out=${GO_OUT} \
-    --go-grpc_opt=paths=source_relative \
-    ${PROTO_DIR}/docreader.proto
+# 生成Go代码（仅在 protoc-gen-go 可用时执行）
+if command -v protoc-gen-go &> /dev/null; then
+    protoc -I${PROTO_DIR} --go_out=${GO_OUT} \
+        --go_opt=paths=source_relative \
+        --go-grpc_out=${GO_OUT} \
+        --go-grpc_opt=paths=source_relative \
+        ${PROTO_DIR}/docreader.proto
+else
+    echo "protoc-gen-go not found, skipping Go code generation"
+fi
 
 # 修复Python导入问题（MacOS兼容版本）
 if [ "$(uname)" == "Darwin" ]; then