Cleanup: over-engineering pass

- merge /api/uptime + /api/version into /api/health and /api/stats
- collapse RTMP per-codec dispatch into a single CodecParser path
- dedupe STUN attribute walking (ufrag_pair / parse_xor_mapped_address)
- dedupe StreamCodec <-> str0m Codec mapping via StreamCodec::from_str0m
- dedupe bearer token extraction in WHIP handlers
- replace regex charset validation with stdlib checks
- flatten one-field wrappers (WebRtcProxyConfig, HttpServerConfig, ServerInfo)
- remove SessionCookie extractor (only fed debug logs)
- delete dead code: entity ActiveModel helpers, get_stream_session,
  WebrtcProxy::local_addr, _connected flag, commented-out blocks
- drop unused deps: futures, rand, regex, serde_json

crates/server/Cargo.toml

@@ -15,20 +15,17 @@ path = "src/main.rs"
 async-broadcast = "0.7.2"
 bytes = "1"
 dashmap = "6.2.1"
-rand = "0.10.1"
 rml_rtmp = "0.8.0"
 str0m = "0.20.0"
 tokio = { version = "1", features = ["full"] }
 axum = { version = "0.8", features = ["macros"] }
 serde = { version = "1.0.228", features = ["serde_derive"] }
-serde_json = "1.0.150"
 sea-orm = { version = "1", features = [ "sqlx-sqlite", "runtime-tokio-rustls", "macros" ] }
 entity = {path = "../entity"}
 migration = {path = "../migration"}
 argon2 = "0.5.3"
 uuid = { version = "1.23.3", features = ["v4"] }
 tower-http = { version = "0.6", features = ["cors"] }
-futures = "0.3.32"
 tracing = "0.1"
 tracing-subscriber = { version = "0.3", features = ["env-filter"] }
 symphonia = { version = "0.5", features = ["aac"] }
@@ -36,7 +33,6 @@ opus = "0.3.1"
 rubato = "3.0.0"
 chrono = "0.4.45"
 time = "0.3"
-regex = "1"
 thiserror = "2.0.18"
 sysinfo = "0.36"
 axum-extra = { version = "0.12.6", features = ["cookie"] }