fix: build image libraries for baseline VPS CPUs

Replace the SIMD-dependent WebAssembly fallback with source-built libvips and Sharp. Pin the libvips archive checksum, use baseline x86-64 compiler flags, retain the native binding and runtime libraries, and check JPEG/PNG/WebP processing before compilation and in the runtime image.

Lint, type checking, and content/security tests passed. Full Docker verification was stopped at the user request; production build and baseline CPU runtime verification remain pending.

next.config.mjs

@@ -5,9 +5,7 @@ const nextConfig = {
   outputFileTracingIncludes: {
     '/*': [
       './migrations/**/*',
-      './node_modules/@img/sharp-wasm32/**/*',
-      './node_modules/@emnapi/runtime/**/*',
-      './node_modules/tslib/**/*',
+      './node_modules/sharp/src/build/Release/*.node',
     ],
   },
   outputFileTracingExcludes: {