initial commit — SIP B2BUA + WebRTC bridge with Rust codec engine

Full-featured SIP router with multi-provider trunking, browser softphone
via WebRTC, real-time Opus/G.722/PCM transcoding in Rust, RNNoise ML
noise suppression, Kokoro neural TTS announcements, and a Lit-based
web dashboard with live call monitoring and REST API.

rust/crates/tts-engine/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "tts-engine"
+version = "0.1.0"
+edition = "2021"
+
+[[bin]]
+name = "tts-engine"
+path = "src/main.rs"
+
+[dependencies]
+kokoro-tts = { version = "0.3", default-features = false }
+# Pin to rc.11 matching kokoro-tts's expectation; enable vendored TLS to avoid system libssl-dev.
+ort = { version = "=2.0.0-rc.11", default-features = false, features = [
+    "std", "download-binaries", "copy-dylibs", "ndarray",
+    "tls-native-vendored"
+] }
+tokio = { version = "1", features = ["rt-multi-thread", "macros"] }
+hound = "3.5"