add thumbnail generation

package-lock.json

@@ -11,7 +11,8 @@
       "dependencies": {
         "next": "^15.5.14",
         "react": "^19.2.4",
-        "react-dom": "^19.2.4"
+        "react-dom": "^19.2.4",
+        "sharp": "^0.34.5"
       },
       "devDependencies": {
         "@tailwindcss/postcss": "^4.2.2",
@@ -545,7 +546,6 @@
       "resolved": "https://registry.npmjs.org/@img/colour/-/colour-1.1.0.tgz",
       "integrity": "sha512-Td76q7j57o/tLVdgS746cYARfSyxk8iEfRxewL9h4OMzYhbW4TAcppl0mT4eyqXddh6L/jwoM75mo7ixa/pCeQ==",
       "license": "MIT",
-      "optional": true,
       "engines": {
         "node": ">=18"
       }
@@ -2906,7 +2906,6 @@
       "version": "2.1.2",
       "resolved": "https://registry.npmjs.org/detect-libc/-/detect-libc-2.1.2.tgz",
       "integrity": "sha512-Btj2BOOO83o3WyH59e8MgXsxEQVcarkUOpEYrubB0urwnN10yQ364rsiByU11nZlqWYZm05i/of7io4mzihBtQ==",
-      "devOptional": true,
       "license": "Apache-2.0",
       "engines": {
         "node": ">=8"
@@ -5780,7 +5779,6 @@
       "version": "7.7.4",
       "resolved": "https://registry.npmjs.org/semver/-/semver-7.7.4.tgz",
       "integrity": "sha512-vFKC2IEtQnVhpT78h1Yp8wzwrf8CM+MzKMHGJZfBtzhZNycRFnXsHk6E5TxIkkMsgNS7mdX3AGB7x2QM2di4lA==",
-      "devOptional": true,
       "license": "ISC",
       "bin": {
         "semver": "bin/semver.js"
@@ -5844,7 +5842,6 @@
       "integrity": "sha512-Ou9I5Ft9WNcCbXrU9cMgPBcCK8LiwLqcbywW3t4oDV37n1pzpuNLsYiAV8eODnjbtQlSDwZ2cUEeQz4E54Hltg==",
       "hasInstallScript": true,
       "license": "Apache-2.0",
-      "optional": true,
       "dependencies": {
         "@img/colour": "^1.0.0",
         "detect-libc": "^2.1.2",