chore: upgrade i18next 26, prettier 3, fontsource-variable, domhandler 6, lint-staged 17

- i18next 23->26 + react-i18next 15->17
- prettier 2->3, reformat all files
- replace @fontsource/inter with @fontsource-variable/inter 5, update import path
- domhandler 5->6 (aligns with transitive deps)
- lint-staged 16->17

vite.config.js

@@ -55,7 +55,7 @@ function serverMatrixSdkCryptoWasm(wasmFilePath) {
         if (req.url === wasmFilePath) {
           const resolvedPath = path.join(
             path.resolve(),
-            '/node_modules/@matrix-org/matrix-sdk-crypto-wasm/pkg/matrix_sdk_crypto_wasm_bg.wasm'
+            '/node_modules/@matrix-org/matrix-sdk-crypto-wasm/pkg/matrix_sdk_crypto_wasm_bg.wasm',
           );
 
           if (fs.existsSync(resolvedPath)) {