migrate from astro+netlify to tanstack start + self-hosted

Replace the Astro static site with a TanStack Start (Bun runtime) app and
add Dockerfile + compose files so the site can be served from home-main-2
behind the home-reverse-proxy-1 Caddy instead of Netlify. CI workflow
rewritten to build a container image and SSH-deploy to the home host.

package.json

@@ -1,20 +1,42 @@
 {
-  "name": "@unom/website",
-  "type": "module",
-  "version": "0.0.1",
-  "scripts": {
-    "dev": "astro dev",
-    "build": "astro build",
-    "preview": "astro preview",
-    "astro": "astro"
-  },
-  "dependencies": {
-    "@astrojs/mdx": "^4.3.0",
-    "@fontsource/inter": "^5.2.5",
-    "@tailwindcss/vite": "^4.1.3",
-    "astro": "^5.8.0",
-    "class-variance-authority": "^0.7.1",
-    "tailwind-merge": "^3.3.0",
-    "tailwindcss": "^4.1.3"
-  }
-}
+	"name": "@unom/website",
+	"private": true,
+	"type": "module",
+	"imports": {
+		"#/*": "./src/*"
+	},
+	"scripts": {
+		"dev": "vite dev --port 3000 --host",
+		"build": "vite build",
+		"start": "bun .output/server/index.mjs",
+		"typecheck": "tsc --noEmit",
+		"format": "biome format",
+		"lint": "biome lint",
+		"check": "biome check"
+	},
+	"dependencies": {
+		"@fontsource/inter": "^5.2.5",
+		"@tailwindcss/vite": "^4.3.0",
+		"@tanstack/react-router": "latest",
+		"@tanstack/react-start": "latest",
+		"@tanstack/router-plugin": "^1.168.9",
+		"class-variance-authority": "^0.7.1",
+		"clsx": "^2.1.1",
+		"nitro": "^3.0.260429-beta",
+		"react": "^19.2.6",
+		"react-dom": "^19.2.6",
+		"react-markdown": "^9.0.3",
+		"tailwind-merge": "^3.6.0",
+		"tailwindcss": "^4.3.0"
+	},
+	"devDependencies": {
+		"@biomejs/biome": "2.4.15",
+		"@types/node": "^25.9.1",
+		"@types/react": "^19.2.15",
+		"@types/react-dom": "^19.2.3",
+		"@vitejs/plugin-react": "^6.0.2",
+		"typescript": "^6.0.3",
+		"vite": "^8.0.14",
+		"vite-tsconfig-paths": "^6.1.1"
+	}
+}