Update dependencies and fix what the new lint rules caught

Every package moves to its newest in-major version, plus React 19.3, @convex-dev/auth 0.0.96 and next-plausible 4. The backend declares @auth/core and generates sign-in codes without oslo, which @convex-dev/auth no longer pulls in. The UseSend patch now actually removes the crypto import Convex refuses to bundle. The stricter react-hooks and typescript-eslint rules flagged the carousel, chart, image crop and mobile hook, which now pass.

packages/backend/convex/_generated/server.js

@@ -91,3 +91,11 @@ export const internalAction = internalActionGeneric;
  * @returns The wrapped function. Import this function from `convex/http.js` and route it to hook it up.
  */
 export const httpAction = httpActionGeneric;
+
+/**
+ * Typesafe environment variables.
+ *
+ * This includes platform-provided env vars and any variables declared in
+ * `convex.config.ts`.
+ */
+export const env = process.env;