feat: enhance HTTP/2 Cleartext (h2c) configuration options

deploy/.env.example

@@ -20,9 +20,30 @@ SERVER_PORT=8080
 # Server mode: release or debug
 SERVER_MODE=release
 
+# Global max request body size in bytes (default: 100MB)
+# 全局最大请求体大小（字节，默认 100MB）
+# Applies to all requests, especially important for h2c first request memory protection
+# 适用于所有请求，对 h2c 第一请求的内存保护尤为重要
+SERVER_MAX_REQUEST_BODY_SIZE=104857600
+
 # Enable HTTP/2 Cleartext (h2c) for client connections
 # 启用 HTTP/2 Cleartext (h2c) 客户端连接
-SERVER_ENABLE_H2C=true
+SERVER_H2C_ENABLED=true
+# H2C max concurrent streams (default: 50)
+# H2C 最大并发流数量（默认 50）
+SERVER_H2C_MAX_CONCURRENT_STREAMS=50
+# H2C idle timeout in seconds (default: 75)
+# H2C 空闲超时时间（秒，默认 75）
+SERVER_H2C_IDLE_TIMEOUT=75
+# H2C max read frame size in bytes (default: 1048576 = 1MB)
+# H2C 最大帧大小（字节，默认 1048576 = 1MB）
+SERVER_H2C_MAX_READ_FRAME_SIZE=1048576
+# H2C max upload buffer per connection in bytes (default: 2097152 = 2MB)
+# H2C 每个连接的最大上传缓冲区（字节，默认 2097152 = 2MB）
+SERVER_H2C_MAX_UPLOAD_BUFFER_PER_CONNECTION=2097152
+# H2C max upload buffer per stream in bytes (default: 524288 = 512KB)
+# H2C 每个流的最大上传缓冲区（字节，默认 524288 = 512KB）
+SERVER_H2C_MAX_UPLOAD_BUFFER_PER_STREAM=524288
 
 # 运行模式: standard (默认) 或 simple (内部自用)
 # standard: 完整 SaaS 功能，包含计费/余额校验；simple: 隐藏 SaaS 功能并跳过计费/余额校验