Support React 19 in svelte-react wrapper

[fallaciousreasoning]

React 19's @types/react removed the global JSX namespace (use React.JSX instead) and removed the zero-argument useRef overload. Import the JSX namespace explicitly from 'react' and provide an initial value to useRef so the wrapper compiles against both @types/react 18 and 19.

[github-actions]

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✅ PR tip preview: https://1418.pr-nala.s.brave.dev/
✅ Commit preview: https://1418.pr-nala.s.brave.dev/commit-860ce2ad5cecc41995b2e98c4005217c562c735e/

- ./tokens/css/variables-android.old.css: 1850 bytes
+ ./tokens/css/variables-android.css: 1850 bytes
---
- ./tokens/css/variables-browser.old.css: 1438 bytes
+ ./tokens/css/variables-browser.css: 1438 bytes
---
- ./tokens/css/variables-ios.old.css: 16941 bytes
+ ./tokens/css/variables-ios.css: 16941 bytes
---
- ./tokens/css/variables-marketing.old.css: 20053 bytes
+ ./tokens/css/variables-marketing.css: 20053 bytes
---
- ./tokens/css/variables-news.old.css: 526 bytes
+ ./tokens/css/variables-news.css: 526 bytes
---
- ./tokens/css/variables-newtab.old.css: 2119 bytes
+ ./tokens/css/variables-newtab.css: 2119 bytes
---
- ./tokens/css/variables-search.old.css: 26893 bytes
+ ./tokens/css/variables-search.css: 26893 bytes
---
- ./tokens/css/variables-web3.old.css: 893 bytes
+ ./tokens/css/variables-web3.css: 893 bytes
---
- ./tokens/css/variables.old.css: 125552 bytes
+ ./tokens/css/variables.css: 125552 bytes

Variables Diff: variables-android.diff

--- ./tokens/css/variables-android.old.css	2026-07-02 23:29:08.522438947 +0000
+++ ./tokens/css/variables-android.css	2026-07-02 23:28:34.074708955 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Jul 01 2026 09:34:07 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Jul 02 2026 23:28:34 GMT+0000 (Coordinated Universal Time)
  */
 
 :root {

Variables Diff: variables-browser.diff

--- ./tokens/css/variables-browser.old.css	2026-07-02 23:29:08.803682803 +0000
+++ ./tokens/css/variables-browser.css	2026-07-02 23:28:34.069708890 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Jul 01 2026 09:34:07 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Jul 02 2026 23:28:34 GMT+0000 (Coordinated Universal Time)
  */
 
 :root {

Variables Diff: variables-ios.diff

--- ./tokens/css/variables-ios.old.css	2026-07-02 23:29:09.111156698 +0000
+++ ./tokens/css/variables-ios.css	2026-07-02 23:28:34.087709125 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Jul 01 2026 09:34:07 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Jul 02 2026 23:28:34 GMT+0000 (Coordinated Universal Time)
  */
 
 :root {

Variables Diff: variables-marketing.diff

--- ./tokens/css/variables-marketing.old.css	2026-07-02 23:29:09.380159956 +0000
+++ ./tokens/css/variables-marketing.css	2026-07-02 23:28:34.121709569 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Jul 01 2026 09:34:07 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Jul 02 2026 23:28:34 GMT+0000 (Coordinated Universal Time)
  */
 
 :root {

Variables Diff: variables-news.diff

--- ./tokens/css/variables-news.old.css	2026-07-02 23:29:09.538332445 +0000
+++ ./tokens/css/variables-news.css	2026-07-02 23:28:34.180710340 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Jul 01 2026 09:34:07 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Jul 02 2026 23:28:34 GMT+0000 (Coordinated Universal Time)
  */
 
 :root {

Variables Diff: variables-newtab.diff

--- ./tokens/css/variables-newtab.old.css	2026-07-02 23:29:09.794416009 +0000
+++ ./tokens/css/variables-newtab.css	2026-07-02 23:28:34.191710483 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Jul 01 2026 09:34:07 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Jul 02 2026 23:28:34 GMT+0000 (Coordinated Universal Time)
  */
 
 :root {

Variables Diff: variables-search.diff

--- ./tokens/css/variables-search.old.css	2026-07-02 23:29:09.997167427 +0000
+++ ./tokens/css/variables-search.css	2026-07-02 23:28:34.157710039 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Jul 01 2026 09:34:07 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Jul 02 2026 23:28:34 GMT+0000 (Coordinated Universal Time)
  */
 
 :root {

Variables Diff: variables-web3.diff

--- ./tokens/css/variables-web3.old.css	2026-07-02 23:29:10.297333915 +0000
+++ ./tokens/css/variables-web3.css	2026-07-02 23:28:34.196710549 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Jul 01 2026 09:34:07 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Jul 02 2026 23:28:34 GMT+0000 (Coordinated Universal Time)
  */
 
 @media (prefers-color-scheme: light) {

Variables Diff: variables.diff

--- ./tokens/css/variables.old.css	2026-07-02 23:29:10.697175905 +0000
+++ ./tokens/css/variables.css	2026-07-02 23:28:33.956707414 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Jul 01 2026 09:34:07 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Jul 02 2026 23:28:33 GMT+0000 (Coordinated Universal Time)
  */
 
 :root {