fix(mcp): annotate undici/DOM type-bridge double-casts in pinned-fetch

Strict audit was failing on two new `as unknown as` casts in pinned-fetch.ts.
They bridge DOM `RequestInit`/`Response` ↔ undici equivalents (structurally
compatible at runtime since Node's global fetch is undici) and are required
to satisfy the FetchLike contract. Annotate so they count as documented
exemptions instead of new violations.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: waleedlatif1

apps/sim/lib/mcp/pinned-fetch.ts

@@ -27,10 +27,12 @@ export function createMcpPinnedFetch(resolvedIP: string): FetchLike {
     // Cast the init through unknown to bridge the typing without losing the
     // critical `dispatcher` typing on the call itself.
     const undiciInit: UndiciRequestInit = {
+      // double-cast-allowed: DOM RequestInit and undici RequestInit are structurally compatible at runtime (Node's global fetch IS undici) but the TS types differ
       ...(init as unknown as UndiciRequestInit),
       dispatcher,
     }
     const response = await undiciFetch(url as string | URL, undiciInit)
+    // double-cast-allowed: undici Response and DOM Response are structurally compatible at runtime; bridging the types is required to satisfy the FetchLike contract
     return response as unknown as Response
   }) satisfies FetchLike
 }