feat: Add initial deployment setup for OTSSignsOrchestrator

- Create index.html for the web application interface.
- Implement deploy.sh script for building and deploying the application to a Docker Swarm manager.
- Add docker-compose.yml for defining application and PostgreSQL service configurations.

Dockerfile

@@ -0,0 +1,51 @@
+# ── Stage 1: Build React frontend ────────────────────────────────────────────
+FROM node:20-alpine AS frontend-build
+WORKDIR /app/ClientApp
+COPY OTSSignsOrchestrator/ClientApp/package.json OTSSignsOrchestrator/ClientApp/package-lock.json* ./
+RUN npm ci
+COPY OTSSignsOrchestrator/ClientApp/ ./
+# Build outputs to ../wwwroot (relative to ClientApp)
+RUN npm run build
+
+# ── Stage 2: Publish .NET app ─────────────────────────────────────────────────
+FROM mcr.microsoft.com/dotnet/sdk:9.0 AS dotnet-build
+WORKDIR /src
+
+# Restore dependencies (layer-cached separately for fast rebuilds)
+COPY OTSSignsOrchestrator/OTSSignsOrchestrator.csproj OTSSignsOrchestrator/
+RUN dotnet restore OTSSignsOrchestrator/OTSSignsOrchestrator.csproj
+
+# Copy source (excluding ClientApp — frontend handled in stage 1)
+COPY OTSSignsOrchestrator/ OTSSignsOrchestrator/
+
+# Copy built frontend assets from stage 1
+COPY --from=frontend-build /app/wwwroot OTSSignsOrchestrator/wwwroot/
+
+RUN dotnet publish OTSSignsOrchestrator/OTSSignsOrchestrator.csproj \
+    -c Release \
+    -o /app/publish \
+    --no-restore
+
+# ── Stage 3: Runtime image ────────────────────────────────────────────────────
+FROM mcr.microsoft.com/dotnet/aspnet:9.0 AS runtime
+WORKDIR /app
+
+# LibGit2Sharp requires git native libraries (libgit2 is bundled in the NuGet package,
+# but git2-ssh requires libssh2 on Linux)
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    libssl3 \
+    ca-certificates \
+    && rm -rf /var/lib/apt/lists/*
+
+COPY --from=dotnet-build /app/publish .
+
+# Data Protection keys must survive restarts — mount a volume here
+VOLUME ["/app/dataprotection-keys"]
+
+# Expose HTTP only — use a reverse proxy (nginx/Caddy/Traefik) for TLS termination
+EXPOSE 8080
+
+ENV ASPNETCORE_URLS=http://+:8080
+ENV ASPNETCORE_ENVIRONMENT=Production
+
+ENTRYPOINT ["dotnet", "OTSSignsOrchestrator.dll"]