feat(files): @shade/files 0.3.0 — E2EE filesystem RPC primitive

M-Files-1..6 land the full files-RPC layer + everything 0.3.0 needs to
ship. Apps keep their own UI; this layer ships the typed RPC, the
streams bridge for content I/O, and production hooks (rate limit,
retention, fingerprint gate, metrics).

@shade/files (NEW)
- Standard ops: list/stat/mkdir/delete/move/read/write/getThumbnail with
  Zod-validated wire schemas + clean user-handler types.
- Custom ops: typed via TypeScript declaration merging on CustomOpsMap
  + per-op Zod schemas; client.custom('app.foo', {...}) is fully typed.
- Content I/O: inline (≤ 256 KiB plaintext) base64-in-RPC; streams
  (> 256 KiB) ride @shade/transfer via userMetadata.shadeFilesWriteId
  / shadeFilesReadStreamId correlation. Server-side TransformStream
  bridges accept inbound transfers immediately (engine rejects chunks
  that arrive before accept) and park the readable for the matching
  RPC.
- Directory ops: walk(path, opts) async-iterable depth-first walker;
  uploadDirectory()/downloadDirectory() with bounded concurrency pool
  (default 4, cap 16), aggregated progress, abort.
- Production hooks (callback-based, vendor-neutral): rate-limit (op +
  byte), idempotency cache (LRU + TTL + in-flight de-dupe), path
  policy (traversal + percent-decode hardening), fingerprint gate
  (required/optional/reject), pluggable Ed25519 sig verification with
  ±5 min replay window, onMetric sink (standard names).
- React hooks (subpath @shade/files/react): ShadeFilesProvider,
  useShadeFiles, useFileList, useFileTransfer/Upload/Download.
- Shade.files.serve(handler) + Shade.files.client(peer) high-level
  entrypoint in @shade/sdk; lazy + memoized; one handler per Shade.

Wire format bump
- @shade/proto wire VERSION 0x01 → 0x02. Length prefixes changed from
  u16 to u32. The previous u16 silently truncated payloads above
  64 KiB — a hard correctness ceiling that blocked inline file ops
  up to 256 KiB. Wire-incompatible with 0.2.x peers; new sessions
  only. Cross-platform Kotlin port (android/shade-android) updated to
  match; test-vectors/wire-format.json regenerated.

Concurrency safety
- ShadeSessionManager.encrypt/.decrypt now run under per-peer mutex.
  Concurrent decryptions of the same peer raced ratchet state
  (manifested as sporadic "Failed to decrypt — wrong key or tampered
  data" under load — surfaced once concurrent uploadDirectory pumped
  many writes in flight). Encrypt was already serialized via
  Shade.send's encryptChains; decrypt is now serialized at the
  manager layer too.

@shade/streams extension
- StreamMetadata.userMetadata?: Record<string, string> for
  application-level key/value pairs that round-trip verbatim through
  stream-init plaintext. Used by @shade/files for write/read
  correlation; available to any consumer.

@shade/sdk extension
- Shade.files getter (lazy + memoized).
- BackgroundHooks.onPruneFiles + periodic timer (default 5 min) +
  BackgroundTasks.setHook(name, fn) for runtime hook registration.

Bundles in-flight 0.2.0 work
- packages/shade-streams/, packages/shade-transfer/, related
  shade-sdk streams-bridge + shade-widgets transfer hooks were
  uncommitted prior to this session. Including them keeps the
  workspace consistent at 0.3.0 since @shade/files depends on them.

Tests
- 74 new tests in @shade/files (572 → 646 workspace pass; 0 fail;
  3× stable). Coverage spans unit (inline-threshold + concurrency),
  integration (read-write inline + streams up to 1 MiB, walk +
  upload/download directory, custom-op, metrics, SDK namespace
  end-to-end), and security (tampered-envelope sig verification,
  replay window, fingerprint gate, rate-limit + quota).

Release artifacts
- All packages bumped to 0.3.0 via scripts/bump-version.ts.
- scripts/publish-all.ts PACKAGES updated with shade-files in
  topological order (after shade-transfer, before shade-sdk).
- bun run publish:dry clean (14 packed, 0 failed).
- examples/08-files-browser/ — three-process CLI demo (prekey + Bob
  server + Alice CLI) covering list/stat/mkdir/delete/upload/download.
- docs/files.md — full API + design doc.
- CHANGELOG.md 0.3.0 entry.

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

packages/shade-transfer/tests/resume.test.ts

@@ -0,0 +1,152 @@
+import { describe, test, expect } from 'bun:test';
+import { SubtleCryptoProvider } from '@shade/crypto-web';
+import { sha256Once } from '@shade/streams';
+import {
+  TransferEngine,
+  MemoryControlChannel,
+  MemoryResumeStore,
+  ShadeTransferHttpTransport,
+  createTransferRoutes,
+  type TransferHandle,
+  type TransferResult,
+} from '../src/index.js';
+
+const crypto = new SubtleCryptoProvider();
+
+function hex(b: Uint8Array): string {
+  return Array.from(b, (x) => x.toString(16).padStart(2, '0')).join('');
+}
+
+describe('Resume protocol — kill-restart-verify', () => {
+  test('sender crash mid-transfer → resumeUpload completes the same stream', async () => {
+    const senderResumeStore = new MemoryResumeStore();
+    // Stable deviceKey shared across engine instances — simulates a stable
+    // identity-derived key. In real use this is `deriveDeviceKey(identity)`.
+    const deviceKey = crypto.randomBytes(32);
+
+    // Receiver is a single, long-lived engine. Its in-memory IncomingState
+    // already tracks accepted chunks; we don't need to persist receiver state
+    // for the in-process scenario.
+    const { a: ctrlA, b: ctrlB } = MemoryControlChannel.linked('alice', 'bob');
+    const receiverEngine = new TransferEngine({
+      crypto,
+      controlChannel: ctrlB,
+      transport: {
+        probe: async () => undefined,
+        sendChunk: async () => {
+          throw new Error('receiver-side sendChunk should not be called');
+        },
+        fetchResumeState: async () => null,
+      },
+      myAddress: 'bob',
+    });
+    const receiverApp = await createTransferRoutes(receiverEngine);
+    const port = 22000 + Math.floor(Math.random() * 500);
+    const server = Bun.serve({ port, fetch: receiverApp.fetch });
+    const baseUrl = `http://localhost:${port}`;
+
+    // Receiver accepts incoming.
+    let resolveRecv!: (h: TransferHandle) => void;
+    const recvHandlePromise = new Promise<TransferHandle>((r) => {
+      resolveRecv = r;
+    });
+    receiverEngine.onIncomingTransfer(async (incoming) => {
+      const h = await incoming.accept({ output: { kind: 'buffer' } });
+      resolveRecv(h);
+    });
+
+    // Sender #1 — this one will "crash" partway through.
+    const senderEngine1 = new TransferEngine({
+      crypto,
+      controlChannel: ctrlA,
+      transport: new ShadeTransferHttpTransport({
+        resolveBaseUrl: async () => baseUrl,
+        authenticator: {
+          signChunk: async () => ({ 'X-Shade-Sender-Address': 'alice' }),
+          signControl: async () => ({ 'X-Shade-Sender-Address': 'alice' }),
+        },
+      }),
+      myAddress: 'alice',
+      resumeStore: senderResumeStore,
+      deviceKey,
+    });
+
+    const input = crypto.randomBytes(256 * 1024); // 256 KiB
+
+    // Start an upload that will be intentionally interrupted. We pause the
+    // sender by aborting the upload after ~25% bytes. The receiver still
+    // holds its IncomingState — chunks already accepted stay tracked.
+    const abort = new AbortController();
+    let bytesAtAbort = 0;
+    const handle1 = await senderEngine1.upload({
+      to: 'bob',
+      input,
+      lanes: 4,
+      chunkSize: 8 * 1024,
+      partition: 'range',
+      signal: abort.signal,
+      onProgress: (p) => {
+        if (p.bytesSent > input.length / 4 && bytesAtAbort === 0) {
+          bytesAtAbort = p.bytesSent;
+          abort.abort();
+        }
+      },
+    });
+    const streamId = handle1.streamId;
+
+    // Wait for the upload to fail (abort).
+    let firstErrCaught = false;
+    try {
+      await handle1.done();
+    } catch {
+      firstErrCaught = true;
+    }
+    expect(firstErrCaught).toBe(true);
+    expect(bytesAtAbort).toBeGreaterThan(0);
+
+    // Tear down the first sender engine — simulates a crashed/restarted client.
+    senderEngine1.destroy();
+
+    // Sender #2 — fresh engine, same resume store.
+    const senderEngine2 = new TransferEngine({
+      crypto,
+      controlChannel: ctrlA, // re-use the link; in real life this would
+      transport: new ShadeTransferHttpTransport({
+        resolveBaseUrl: async () => baseUrl,
+        authenticator: {
+          signChunk: async () => ({ 'X-Shade-Sender-Address': 'alice' }),
+          signControl: async () => ({ 'X-Shade-Sender-Address': 'alice' }),
+        },
+      }),
+      myAddress: 'alice',
+      resumeStore: senderResumeStore,
+      deviceKey,
+    });
+
+    // Verify state is still in the resume store.
+    const persisted = await senderResumeStore.get(streamId);
+    expect(persisted).not.toBeNull();
+    expect(persisted!.status).toBe('active');
+
+    // Resume the upload with the same input bytes.
+    const handle2 = await senderEngine2.resumeUpload(streamId, input);
+    const senderResult = await handle2.done();
+    expect(senderResult.streamId).toBe(streamId);
+
+    // Receiver finishes too.
+    const recvHandle = await recvHandlePromise;
+    const recvResult = await recvHandle.done();
+    const received =
+      (recvResult as TransferResult & { bytes?: Uint8Array }).bytes ?? new Uint8Array();
+    expect(received).toEqual(input);
+    expect(senderResult.sha256).toBe(hex(sha256Once(input)));
+
+    // Persisted state should now be finished.
+    const after = await senderResumeStore.get(streamId);
+    expect(after?.status).toBe('finished');
+
+    senderEngine2.destroy();
+    receiverEngine.destroy();
+    server.stop();
+  }, 30_000);
+});