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-server/src/events.ts

@@ -86,7 +86,9 @@ export class PrekeyServerEvents {
  * Uses SHA-256 via crypto.subtle directly.
  */
 export async function shortHash(key: Uint8Array): Promise<string> {
-  const buf = await globalThis.crypto.subtle.digest('SHA-256', key);
+  // Cast through ArrayBuffer (rather than DOM `BufferSource`) so this file
+  // type-checks without DOM lib in the consumer's tsconfig.
+  const buf = await globalThis.crypto.subtle.digest('SHA-256', key as unknown as ArrayBuffer);
   const arr = new Uint8Array(buf).slice(0, 8);
   return Array.from(arr, (b) => b.toString(16).padStart(2, '0')).join('');
 }

packages/shade-server/src/index.ts

@@ -31,10 +31,14 @@ export function createPrekeyServer(options: {
   events?: PrekeyServerEvents;
 }): Hono {
   const store = options.store ?? new MemoryPrekeyStore();
-  return createPrekeyRoutes(store, options.crypto, {
-    disableRateLimit: options.disableRateLimit,
-    events: options.events,
-  });
+  const routesOptions: Parameters<typeof createPrekeyRoutes>[2] = {};
+  if (options.disableRateLimit !== undefined) {
+    routesOptions.disableRateLimit = options.disableRateLimit;
+  }
+  if (options.events !== undefined) {
+    routesOptions.events = options.events;
+  }
+  return createPrekeyRoutes(store, options.crypto, routesOptions);
 }
 
 export { RateLimiter, MemoryRateLimitStore } from './rate-limit.js';

packages/shade-server/src/routes.ts

@@ -1,6 +1,6 @@
 import { Hono } from 'hono';
 import type { CryptoProvider } from '@shade/core';
-import { fromBase64, errorToHttpStatus, ShadeError, ValidationError, RateLimitError } from '@shade/core';
+import { errorToHttpStatus, ShadeError, ValidationError, RateLimitError } from '@shade/core';
 import type { PrekeyStore } from './store.js';
 import { verifyPayload, validateAddress } from './auth.js';
 import { RateLimiter, MemoryRateLimitStore, REGISTER_LIMIT, FETCH_LIMIT, REPLENISH_LIMIT, DELETE_LIMIT } from './rate-limit.js';