release(v4.0.2): consumer-strict reader-shape fixes

4.0.1's typecheck gate compiled each package internally against
lib: ["ES2022"]. That doesn't catch types that only fail when
*consumer* code (lib: ["DOM"] + exactOptionalPropertyTypes) tries to
assign a native browser type into one of our locally-defined narrower
types. Dispatch hit one such case in @shade/files inline-threshold.ts.

This release adds a tests/consumer-strict/ smoke project to the
pre-publish gate. It compiles a tiny "as if I were a downstream app"
TS file against:

  lib: ["ES2022", "DOM", "DOM.Iterable"]
  types: ["bun-types"]
  exactOptionalPropertyTypes: true
  strict: true
  paths → packages/*/src/index.ts

scripts/typecheck-all.ts now runs the smoke after per-package checks.
Both must pass before publish:dry / publish:all proceeds.

### Fixed
- @shade/files inline-threshold.ts: MinimalReader<T> rewritten as the
  explicit disjoint union { done:false, value:T } | { done:true,
  value?: T | undefined } that's assignable from every native reader
  shape (bun, DOM, node:stream/web). Fixes the
  "ReadableStreamReadResult is not assignable" Dispatch reported.
- @shade/files streams-bridge (client + server): stash setTimeout
  return in a local before .unref?.() via { unref?: () => void } cast.
  Fluent .unref?.() failed under lib: ["DOM"] (setTimeout returns
  number there).
- @shade/sdk background.ts: same setInterval .unref?.() fix.

Wire-compatible. No API shape changed.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/shade-files/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@shade/files",
-  "version": "4.0.1",
+  "version": "4.0.2",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",

packages/shade-files/src/client/inline-threshold.ts

@@ -161,15 +161,33 @@ async function peekStream(stream: ReadableStream<Uint8Array>): Promise<InlineDec
   }
 }
 
-interface MinimalReader {
-  read(): Promise<{ value: Uint8Array | undefined; done: boolean }>;
+/**
+ * Structural mirror of WHATWG `ReadableStreamDefaultReader<Uint8Array>`.
+ *
+ * The disjoint union shape with `value?: T | undefined` is the lowest
+ * common denominator across every lib environment we care about:
+ * - `bun-types` emits `{ done: true; value?: undefined }`
+ * - `lib.dom`   emits `{ done: true; value?: T }`
+ * - `node:stream/web` emits the union form
+ *
+ * `value?: T | undefined` is assignable from all three. A flat
+ * `{ value?: T; done: boolean }` is rejected by
+ * `exactOptionalPropertyTypes` because the present branches require
+ * `value: T`. Defining it as an explicit union avoids the trap.
+ */
+type MinimalReadResult<T> =
+  | { done: false; value: T }
+  | { done: true; value?: T | undefined };
+
+interface MinimalReader<T> {
+  read(): Promise<MinimalReadResult<T>>;
   cancel(reason?: unknown): Promise<void>;
   releaseLock(): void;
 }
 
 function reconstructStream(
   prefix: Uint8Array[],
-  reader: MinimalReader,
+  reader: MinimalReader<Uint8Array>,
 ): ReadableStream<Uint8Array> {
   let prefixIdx = 0;
   return new ReadableStream<Uint8Array>({

packages/shade-files/src/client/streams-bridge.ts

@@ -142,13 +142,14 @@ export async function createClientStreamsBridge(
     }
 
     parked.set(readStreamId, arrival);
-    setTimeout(() => {
+    const t = setTimeout(() => {
       const stale = parked.get(readStreamId);
       if (stale === arrival) {
         parked.delete(readStreamId);
         void handle.abort('rpc-timeout').catch(() => undefined);
       }
-    }, parkedReadTtlMs).unref?.();
+    }, parkedReadTtlMs);
+    (t as unknown as { unref?: () => void }).unref?.();
   });
 
   function cleanupWaiter(w: PendingReadWaiter): void {

packages/shade-files/src/server/streams-bridge.ts

@@ -168,13 +168,14 @@ export async function createServerStreamsBridge(
 
     // No waiter yet — park.
     parked.set(writeId, arrived);
-    setTimeout(() => {
+    const parkTimer = setTimeout(() => {
       const stale = parked.get(writeId);
       if (stale === arrived) {
         parked.delete(writeId);
         void handle.abort('rpc-timeout').catch(() => undefined);
       }
-    }, parkedWriteTtlMs).unref?.();
+    }, parkedWriteTtlMs);
+    (parkTimer as unknown as { unref?: () => void }).unref?.();
   });
 
   function cleanupWaiter(w: PendingWaiter): void {