Initial commit: ReTeamSpeak cross-platform TeamSpeak client

- tscore: Protocol implementation (packets, crypto, connection handshake)
- tsaudio: Audio engine (capture, playback, codec, VAD, jitter buffer)
- tsdb: SQLite database (identities, bookmarks, messages, settings)
- shared: Core types and events
- tauri-app: Tauri v2 desktop application with React frontend
- docs: SRS, SAD, SDD documentation
- CI/CD: GitHub Actions workflow
- 32 unit tests passing

Dockerfile

@@ -0,0 +1,58 @@
+FROM debian:trixie
+
+# Install system dependencies
+RUN apt-get update && apt-get install -y \
+    curl \
+    pkg-config \
+    build-essential \
+    libdbus-1-dev \
+    libgtk-3-dev \
+    libwebkit2gtk-4.1-dev \
+    libayatana-appindicator3-dev \
+    librsvg2-dev \
+    libssl-dev \
+    libasound2-dev \
+    && rm -rf /var/lib/apt/lists/*
+
+# Install Rust
+RUN curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
+ENV PATH="/root/.cargo/bin:${PATH}"
+
+# Install Node.js (for frontend)
+RUN curl -fsSL https://deb.nodesource.com/setup_20.x | bash - && \
+    apt-get install -y nodejs && \
+    rm -rf /var/lib/apt/lists/*
+
+WORKDIR /app
+
+# Copy Cargo files first for caching
+COPY Cargo.toml ./
+COPY shared/Cargo.toml shared/
+COPY tscore/Cargo.toml tscore/
+COPY tsaudio/Cargo.toml tsaudio/
+COPY tsdb/Cargo.toml tsdb/
+COPY tauri-app/src-tauri/Cargo.toml tauri-app/src-tauri/
+
+# Create dummy source files for dependency caching
+RUN mkdir -p shared/src && echo "pub fn dummy() {}" > shared/src/lib.rs && \
+    mkdir -p tscore/src && echo "pub fn dummy() {}" > tscore/src/lib.rs && \
+    mkdir -p tsaudio/src && echo "pub fn dummy() {}" > tsaudio/src/lib.rs && \
+    mkdir -p tsdb/src && echo "pub fn dummy() {}" > tsdb/src/lib.rs && \
+    mkdir -p tauri-app/src-tauri/src && echo "pub fn dummy() {}" > tauri-app/src-tauri/src/lib.rs
+
+# Build dependencies (cached layer)
+RUN cargo build 2>/dev/null || true
+
+# Copy actual source
+COPY . .
+
+# Build
+RUN cargo build -p shared -p tscore -p tsaudio -p tsdb
+
+# Build frontend
+RUN cd tauri-app/frontend && npm install && npm run build
+
+# Final build
+RUN cargo build
+
+CMD ["cargo", "test", "-p", "shared", "-p", "tscore", "-p", "tsaudio", "-p", "tsdb"]