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-files/tests/unit/canonical.test.ts

@@ -0,0 +1,135 @@
+import { describe, test, expect } from 'bun:test';
+import {
+  canonicalRpcBytes,
+  canonicalJsonStringify,
+  hashArgs,
+  bytesToHex,
+  bytesToBase64,
+  base64ToBytes,
+} from '../../src/index.js';
+
+describe('canonicalJsonStringify', () => {
+  test('sorts object keys', () => {
+    expect(canonicalJsonStringify({ b: 1, a: 2 })).toBe('{"a":2,"b":1}');
+  });
+
+  test('skips undefined values', () => {
+    expect(canonicalJsonStringify({ a: 1, b: undefined, c: 2 })).toBe('{"a":1,"c":2}');
+  });
+
+  test('preserves array order', () => {
+    expect(canonicalJsonStringify([3, 1, 2])).toBe('[3,1,2]');
+  });
+
+  test('recursive sorting', () => {
+    const a = canonicalJsonStringify({ outer: { y: 1, x: 2 } });
+    const b = canonicalJsonStringify({ outer: { x: 2, y: 1 } });
+    expect(a).toBe(b);
+    expect(a).toBe('{"outer":{"x":2,"y":1}}');
+  });
+
+  test('handles primitives', () => {
+    expect(canonicalJsonStringify(null)).toBe('null');
+    expect(canonicalJsonStringify(true)).toBe('true');
+    expect(canonicalJsonStringify(42)).toBe('42');
+    expect(canonicalJsonStringify('hi')).toBe('"hi"');
+  });
+
+  test('different argument orders hash identically', () => {
+    const h1 = hashArgs({ b: 1, a: 2 });
+    const h2 = hashArgs({ a: 2, b: 1 });
+    expect(bytesToHex(h1)).toBe(bytesToHex(h2));
+  });
+
+  test('different values hash differently', () => {
+    expect(bytesToHex(hashArgs({ a: 1 }))).not.toBe(bytesToHex(hashArgs({ a: 2 })));
+  });
+});
+
+describe('canonicalRpcBytes', () => {
+  test('deterministic for same input (known vector)', () => {
+    const args = {
+      address: 'alice',
+      signedAt: 1730000000000,
+      kind: 'shade.fs.list/v1',
+      id: 'AbCdEfGhIjKlMnOpQrStUv',
+      argsHash: new Uint8Array(32).fill(0xab),
+    };
+    const a = canonicalRpcBytes(args);
+    const b = canonicalRpcBytes(args);
+    expect(a).toEqual(b);
+  });
+
+  test('changes when address differs', () => {
+    const base = {
+      signedAt: 1,
+      kind: 'shade.fs.list/v1',
+      id: 'AbCdEfGhIjKlMnOpQrStUv',
+      argsHash: new Uint8Array(32),
+    };
+    const a = canonicalRpcBytes({ ...base, address: 'alice' });
+    const b = canonicalRpcBytes({ ...base, address: 'bob' });
+    expect(a).not.toEqual(b);
+  });
+
+  test('changes when signedAt differs', () => {
+    const base = {
+      address: 'alice',
+      kind: 'shade.fs.list/v1',
+      id: 'AbCdEfGhIjKlMnOpQrStUv',
+      argsHash: new Uint8Array(32),
+    };
+    expect(canonicalRpcBytes({ ...base, signedAt: 1 })).not.toEqual(
+      canonicalRpcBytes({ ...base, signedAt: 2 }),
+    );
+  });
+
+  test('changes when kind differs', () => {
+    const base = {
+      address: 'alice',
+      signedAt: 1,
+      id: 'AbCdEfGhIjKlMnOpQrStUv',
+      argsHash: new Uint8Array(32),
+    };
+    expect(canonicalRpcBytes({ ...base, kind: 'shade.fs.list/v1' })).not.toEqual(
+      canonicalRpcBytes({ ...base, kind: 'shade.fs.stat/v1' }),
+    );
+  });
+
+  test('changes when argsHash differs', () => {
+    const base = {
+      address: 'alice',
+      signedAt: 1,
+      kind: 'shade.fs.list/v1',
+      id: 'AbCdEfGhIjKlMnOpQrStUv',
+    };
+    expect(
+      canonicalRpcBytes({ ...base, argsHash: new Uint8Array(32) }),
+    ).not.toEqual(
+      canonicalRpcBytes({ ...base, argsHash: new Uint8Array(32).fill(1) }),
+    );
+  });
+});
+
+describe('hashArgs', () => {
+  test('produces 32-byte digest', () => {
+    expect(hashArgs({ a: 1 }).length).toBe(32);
+  });
+
+  test('null input is fine', () => {
+    expect(hashArgs(null).length).toBe(32);
+  });
+});
+
+describe('bytesToHex / base64', () => {
+  test('hex roundtrip', () => {
+    const b = new Uint8Array([0x01, 0xab, 0xff, 0x00]);
+    expect(bytesToHex(b)).toBe('01abff00');
+  });
+
+  test('base64 roundtrip', () => {
+    const b = new Uint8Array([1, 2, 3, 4]);
+    const enc = bytesToBase64(b);
+    expect(base64ToBytes(enc)).toEqual(b);
+  });
+});