chore: move fetch directory into shared/lib

src/shared/lib/fetch/index.ts

@@ -0,0 +1,14 @@
+/**
+ * Shared fetch layer exports
+ *
+ * Exports collection caching utilities and reactive patterns for Svelte 5
+ */
+
+export { createCollectionCache } from './collectionCache';
+export type {
+    CacheItemInternalState,
+    CacheOptions,
+    CacheStats,
+    CollectionCacheManager,
+} from './collectionCache';
+export { reactiveQueryArgs } from './reactiveQueryArgs';