Since #35582, the auto-imported $fetch is typed by the fetch.d.ts template as ofetch's plain $fetch, so every call returns Promise<any> with no typed-route inference. This types it as nitro's route-aware $Fetch, matching the runtime cast in #app/composables/fetch.

• emit export declare const $fetch: import('nitro/types').$Fetch from dollarFetchTypeTemplate
• keep build-stub-fetch.d.ts in sync with the template
• add active fixture tests pinning $fetch's type and Promise<unknown> for unmatched routes
• add the Wrong types instead of union when fetching API routes having dynamic and static handler #22488 repro (dynamic + static handlers on one prefix) with union assertions, commented pending Better typed fetch/$fetch and routes nitrojs/nitro#2758

While investigating #22488 I found the remaining blocker is upstream: nitro's generated nitro-imports.d.ts emits import paths like .../node_modules/nitro/h3 (package dir joined with the exports subpath), which doesn't exist on disk. TS can't resolve it and skipLibCheck hides the error, so defineEventHandler becomes any and poisons all InternalApi route types. With that patched locally plus this fix, $fetch(/api/posts/${id}) correctly infers Promise<number | string>.

🔗 Linked issue: #22488