Merge m5max128gitea Web GUI + Backup features with local SMB fixes

Merged from m5max128gitea:
- Web GUI Phase 11: User/Share/Dashboard management
- NFS stub + nfsserve dependency
- Backup/Snapshot REST API endpoints
- Integration tests for user/share management
- Feature comparison docs (Proxmox/Unraid/OpenNAS)

Preserved from local:
- upload_path config (tested stable)
- delete_file/preview_file routes (MyFiles)
- SSH async I/O
- auth.sqlite (important user data)
- Admin WebDAV + CorsLayer

Conflicts resolved:
- AGENTS.md: kept remote (more complete docs)
- myfiles.rs: kept local upload_path
- server.rs: merged both routes (preview + backup)
- auth.sqlite: preserved local (important user data)

markbase-core/Cargo.toml

@@ -51,6 +51,7 @@ axum-extra = { version = "0.9", features = ["multipart"] }
 http = "1"
 tokio-util = { version = "0.7", features = ["io"] }
 zstd = "0.13"
+lz4_flex = "0.11"
 hex = "0.4"
 toml = "0.8"
 uuid = { version = "1", features = ["v4"] }
@@ -89,12 +90,16 @@ tracing-subscriber = { version = "0.3", features = ["env-filter", "json"] }
 # === LDAP Authentication (Phase 2) ===
 ldap3 = { version = "0.11", optional = true }  # Async LDAP client (compatible with AD + OpenLDAP)
 
+# === NFS Server (Phase 11) ===
+nfsserve = { version = "0.11", optional = true }  # NFSv3/NFSv4 server implementation
+
 [features]
 default = []                          # 默认不启用可选格式
 optional-formats = ["unrar", "xz2", "sevenz-rust"]  # 争议格式可选启用
 smb-server = ["dep:smb-server"]       # SMB server feature flag
 async-vfs = ["dep:reqwest"]           # Async VfsBackend trait + native async S3
 ldap = ["dep:ldap3"]                  # LDAP authentication provider
+nfs = ["dep:nfsserve"]                # NFSv3/NFSv4 server feature flag
 
 [dev-dependencies]
 # tempfile moved to dependencies (needed for archive extraction)