Merge feature/server-pro into main

Adds btest-server-pro: multi-user bandwidth test server with SQLite DB,
per-IP quotas (daily/weekly/monthly), inline byte budget enforcement,
TCP multi-connection support, MD5 auth, web dashboard with Chart.js
graphs, quota progress bars, and JSON export.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Cargo.toml

@@ -24,6 +24,15 @@ path = "src/bin/client_only.rs"
 name = "btest-server"
 path = "src/bin/server_only.rs"
 
+[[bin]]
+name = "btest-server-pro"
+path = "src/server_pro/main.rs"
+required-features = ["pro"]
+
+[features]
+default = []
+pro = ["dep:rusqlite", "dep:ldap3", "dep:axum", "dep:tower-http", "dep:serde", "dep:serde_json", "dep:askama"]
+
 [dependencies]
 tokio = { version = "1", features = ["full"] }
 clap = { version = "4", features = ["derive"] }
@@ -40,6 +49,13 @@ num-traits = "0.2.19"
 num-integer = "0.1.46"
 sha2 = "0.11.0"
 hostname = "0.4.2"
+rusqlite = { version = "0.39.0", features = ["bundled"], optional = true }
+ldap3 = { version = "0.12.1", optional = true }
+axum = { version = "0.8.8", features = ["tokio"], optional = true }
+tower-http = { version = "0.6.8", features = ["fs", "cors"], optional = true }
+serde = { version = "1.0.228", features = ["derive"], optional = true }
+serde_json = { version = "1.0.149", optional = true }
+askama = { version = "0.15.6", optional = true }
 
 [profile.release]
 opt-level = 3