实现 MinIO 对象存储图片流水线（可迁移 OSS）

- 新增 S3 兼容 Storage 抽象与 MinIO 实现，compose 启动 MinIO
- 上传接口：校验 → 缩放 → WebP → 主图/缩略图入库
- 消息图片 content 改为对象 URL，拒绝 base64
- 工作台/访客端改为先上传再发消息

server/go.mod

@@ -3,10 +3,13 @@ module kefu-sys/server
 go 1.26.3
 
 require (
+	github.com/chai2010/webp v1.4.0
+	github.com/disintegration/imaging v1.6.2
 	github.com/gin-gonic/gin v1.10.0
 	github.com/golang-jwt/jwt/v5 v5.2.1
 	github.com/gorilla/websocket v1.5.3
-	golang.org/x/crypto v0.28.0
+	github.com/minio/minio-go/v7 v7.2.1
+	golang.org/x/crypto v0.51.0
 	gorm.io/driver/postgres v1.5.9
 	gorm.io/driver/sqlite v1.5.7
 	gorm.io/gorm v1.25.12
@@ -15,14 +18,17 @@ require (
 require (
 	github.com/bytedance/sonic v1.11.6 // indirect
 	github.com/bytedance/sonic/loader v0.1.1 // indirect
+	github.com/cespare/xxhash/v2 v2.3.0 // indirect
 	github.com/cloudwego/base64x v0.1.4 // indirect
 	github.com/cloudwego/iasm v0.2.0 // indirect
+	github.com/dustin/go-humanize v1.0.1 // indirect
 	github.com/gabriel-vasile/mimetype v1.4.3 // indirect
 	github.com/gin-contrib/sse v0.1.0 // indirect
 	github.com/go-playground/locales v0.14.1 // indirect
 	github.com/go-playground/universal-translator v0.18.1 // indirect
 	github.com/go-playground/validator/v10 v10.20.0 // indirect
 	github.com/goccy/go-json v0.10.2 // indirect
+	github.com/google/uuid v1.6.0 // indirect
 	github.com/jackc/pgpassfile v1.0.0 // indirect
 	github.com/jackc/pgservicefile v0.0.0-20221227161230-091c0ba34f0a // indirect
 	github.com/jackc/pgx/v5 v5.5.5 // indirect
@@ -30,22 +36,33 @@ require (
 	github.com/jinzhu/inflection v1.0.0 // indirect
 	github.com/jinzhu/now v1.1.5 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
-	github.com/klauspost/cpuid/v2 v2.2.7 // indirect
+	github.com/klauspost/compress v1.18.6 // indirect
+	github.com/klauspost/cpuid/v2 v2.2.11 // indirect
+	github.com/klauspost/crc32 v1.3.0 // indirect
 	github.com/kr/text v0.2.0 // indirect
 	github.com/leodido/go-urn v1.4.0 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/mattn/go-sqlite3 v1.14.22 // indirect
+	github.com/minio/crc64nvme v1.1.1 // indirect
+	github.com/minio/md5-simd v1.1.2 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
-	github.com/pelletier/go-toml/v2 v2.2.2 // indirect
+	github.com/pelletier/go-toml/v2 v2.3.1 // indirect
+	github.com/philhofer/fwd v1.2.0 // indirect
 	github.com/rogpeppe/go-internal v1.15.0 // indirect
+	github.com/rs/xid v1.6.0 // indirect
+	github.com/tinylib/msgp v1.6.1 // indirect
 	github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
 	github.com/ugorji/go/codec v1.2.12 // indirect
+	github.com/zeebo/xxh3 v1.1.0 // indirect
+	go.yaml.in/yaml/v3 v3.0.4 // indirect
 	golang.org/x/arch v0.8.0 // indirect
-	golang.org/x/net v0.25.0 // indirect
-	golang.org/x/sync v0.8.0 // indirect
-	golang.org/x/sys v0.26.0 // indirect
-	golang.org/x/text v0.19.0 // indirect
-	google.golang.org/protobuf v1.34.1 // indirect
+	golang.org/x/image v0.0.0-20211028202545-6944b10bf410 // indirect
+	golang.org/x/net v0.53.0 // indirect
+	golang.org/x/sync v0.20.0 // indirect
+	golang.org/x/sys v0.44.0 // indirect
+	golang.org/x/text v0.37.0 // indirect
+	google.golang.org/protobuf v1.36.10 // indirect
+	gopkg.in/ini.v1 v1.67.2 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )