Restructure Web App into server/ + web/ (GsmNode parity)

Reorganize the Web App to match the GsmNode project layout: a Go
backend-for-frontend in server/ that embeds the built SPA and reverse-proxies
/api/* to the API Server, with the Vue 3 + Vite frontend moved into web/.

- Move all frontend files into web/ (history preserved via renames)
- Point vite build output at ../server/dist for Go embedding
- Add server/ Go BFF (main.go, go.mod, .env.example, Run-WebApp.ps1)
- Drop Docker/nginx deploy (Dockerfile, docker-compose.yml, nginx.conf.template,
  .dockerignore) in favor of the BFF, matching GsmNode
- Update .claude/launch.json to run the dev server from web/
- Rewrite README.md for the new layout

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Web App/server/Run-WebApp.ps1

@@ -0,0 +1,29 @@
+# Builds the Vue frontend (if needed) and runs the Web App BFF.
+#
+#   ./Run-WebApp.ps1            # build frontend then serve
+#   ./Run-WebApp.ps1 -SkipBuild # serve existing dist only
+
+param([switch]$SkipBuild)
+
+$ErrorActionPreference = "Stop"
+$serverDir = Split-Path -Parent $MyInvocation.MyCommand.Path
+$root = Split-Path -Parent $serverDir   # the "Web App" folder
+$webDir = Join-Path $root "web"
+
+$goBin = "C:\Program Files\Go\bin"
+if (Test-Path $goBin) { $env:Path = "$goBin;$env:Path" }
+
+if (-not $SkipBuild) {
+    Write-Host "Building frontend..." -ForegroundColor Cyan
+    Push-Location $webDir
+    try {
+        if (-not (Test-Path "node_modules")) { npm install }
+        npm run build
+    } finally { Pop-Location }
+}
+
+Push-Location $serverDir
+try {
+    Write-Host "Starting Web App on :8090 (Ctrl+C to stop)..." -ForegroundColor Cyan
+    go run .
+} finally { Pop-Location }