fix: downgrade onnxruntime-web to 1.18 for non-threaded SIMD WASM

ort 1.19+ dropped non-threaded WASM binaries and replaced them with a
threaded .mjs loader that Vite's dev server fails to serve correctly
(wrong MIME type / transform interception). ort 1.18 ships ort-wasm-simd.wasm
which works with numThreads=1 and needs no .mjs dynamic import.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

yarn.lock

@@ -8450,6 +8450,7 @@ __metadata:
     node-stdlib-browser: "npm:^1.3.1"
     normalize.css: "npm:^8.0.1"
     observable-hooks: "npm:^4.2.3"
+    onnxruntime-web: "npm:1.18.0"
     pako: "npm:^2.0.4"
     postcss: "npm:^8.4.41"
     postcss-preset-env: "npm:^10.0.0"
@@ -9635,6 +9636,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"flatbuffers@npm:^1.12.0":
+  version: 1.12.0
+  resolution: "flatbuffers@npm:1.12.0"
+  checksum: 10c0/14f9fb55f3063b389fc4e3d67ee8ffc71e351b478369fdae919701e458fc7766f2fea4f51181d6e73b4930fbc018cb7013558930367811b960cff01f23aae618
+  languageName: node
+  linkType: hard
+
 "flatbuffers@npm:^25.1.24":
   version: 25.9.23
   resolution: "flatbuffers@npm:25.9.23"
@@ -12046,6 +12054,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"onnxruntime-common@npm:1.18.0":
+  version: 1.18.0
+  resolution: "onnxruntime-common@npm:1.18.0"
+  checksum: 10c0/dc5caab4c5b95b4255ba3dcd5ea3e04e10a3a8c605d60c53dac25facfbe9d59a60c510b8ffc3e5f1c8816fded479b6f946b7840a0d10cbd32914ef8ce81c7218
+  languageName: node
+  linkType: hard
+
 "onnxruntime-common@npm:1.24.3":
   version: 1.24.3
   resolution: "onnxruntime-common@npm:1.24.3"
@@ -12053,6 +12068,20 @@ __metadata:
   languageName: node
   linkType: hard
 
+"onnxruntime-web@npm:1.18.0":
+  version: 1.18.0
+  resolution: "onnxruntime-web@npm:1.18.0"
+  dependencies:
+    flatbuffers: "npm:^1.12.0"
+    guid-typescript: "npm:^1.0.9"
+    long: "npm:^5.2.3"
+    onnxruntime-common: "npm:1.18.0"
+    platform: "npm:^1.3.6"
+    protobufjs: "npm:^7.2.4"
+  checksum: 10c0/90d9eed3e8d8bcfea61858eee2a1b94c680c67f6265bb5924752ae1bd9db93cb2dd8bc562ffba6b048fc32c721fcc30fd0b0669da5607fc6c41eaecaba3d4bd7
+  languageName: node
+  linkType: hard
+
 "onnxruntime-web@npm:^1.17.0":
   version: 1.24.3
   resolution: "onnxruntime-web@npm:1.24.3"