release(v4.0.0): Shade GA — V3.x consolidation + audit prep

V3.1 → V3.12 consolidated and tagged for the first GA release. Wire
format unchanged from 0.4.x — 4.0 peers interoperate with 0.4.x peers
byte-for-byte. The version bump is semantic: audit-cycle complete,
opt-in surface fully exposed, threat model refreshed for every new
surface.

Highlights:
- All 24 @shade/* packages bumped to 4.0.0 in lockstep.
- CHANGELOG 4.0.0 section is the canonical manifest of what landed.
- THREAT-MODEL extended (§10 fingerprint gates, §11 WebRTC P2P, §12
  Web-Worker boundary) + residual-risks table refreshed.
- OpenAPI now covers all 27 routes: prekey, transfer, KT, inbox,
  bridge, observer, /metrics, /healthz, /ready.
- MIGRATION 0.3.x → 4.0 documented + smoke-tested against
  shade migrate-storage on a real SQLite DB.
- docs/audit/REVIEW-BUNDLE.md + SCOPE.md ready for external reviewer.
- scripts/soak.ts harness for the GA-stable 2-week soak window.
- All V*.md plans archived under docs/archive/ with Status: Done.
- Voice/Video carved out into V5.0; 4.0 audit focuses on the frozen
  non-realtime stack.

Tests: TS 1000/1000 + Kotlin 11/11 cross-platform vectors green.
Docker: gt.zyon.no/stian/shade-prekey:4.0.0 builds and reports
  version 4.0.0 on /health.

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

packages/shade-transport/tests/kt-transport.test.ts

@@ -0,0 +1,230 @@
+import { describe, test, expect } from 'bun:test';
+import { SubtleCryptoProvider, MemoryStorage } from '@shade/crypto-web';
+import { ShadeSessionManager } from '@shade/core';
+import {
+  createPrekeyServerWithKT,
+  MemoryPrekeyStore,
+} from '@shade/server';
+import {
+  KTVerificationError,
+  LightWitness,
+  MemoryKTLogStore,
+  computeLogId,
+  signSth,
+  type SignedTreeHead,
+} from '@shade/key-transparency';
+import { ShadeFetchTransport } from '../src/fetch-transport.js';
+
+const crypto = new SubtleCryptoProvider();
+
+describe('ShadeFetchTransport with KT verifier', () => {
+  test('fetch verifies inclusion proof against pinned log key', async () => {
+    const logKp = await crypto.generateEd25519KeyPair();
+    const { app, kt } = await createPrekeyServerWithKT({
+      crypto,
+      store: new MemoryPrekeyStore(),
+      disableRateLimit: true,
+      keyTransparency: {
+        store: new MemoryKTLogStore(),
+        signingPrivateKey: logKp.privateKey,
+        signingPublicKey: logKp.publicKey,
+      },
+    });
+
+    const port = 20100 + Math.floor(Math.random() * 500);
+    const handle = Bun.serve({ port, fetch: app.fetch });
+    try {
+      const baseUrl = `http://localhost:${port}`;
+
+      // Bob registers
+      const bobStorage = new MemoryStorage();
+      const bobManager = new ShadeSessionManager(crypto, bobStorage);
+      await bobManager.initialize();
+      const bobIdentity = await bobStorage.getIdentityKeyPair();
+      const bobTransport = new ShadeFetchTransport({
+        baseUrl,
+        crypto,
+        signingPrivateKey: bobIdentity!.signingPrivateKey,
+      });
+      const bobOTPKs = await bobManager.generateOneTimePreKeys(3);
+      const bobBundle = await bobManager.createPreKeyBundle();
+      await bobTransport.register('bob', bobManager.getPublicIdentity(), bobBundle.signedPreKey, bobOTPKs);
+
+      // Alice fetches with KT verifier — should succeed
+      const observed: SignedTreeHead[] = [];
+      const aliceTransport = new ShadeFetchTransport({
+        baseUrl,
+        crypto,
+        keyTransparency: {
+          mode: 'observe-strict',
+          logPublicKey: logKp.publicKey,
+          onObserveSth: async (sth) => {
+            observed.push(sth);
+          },
+        },
+      });
+      const result = await aliceTransport.fetchBundleVerified('bob');
+      expect(result.bundle.identityDHKey).toEqual(bobManager.getPublicIdentity().dhKey);
+      expect(result.ktSth).toBeDefined();
+      expect(result.ktSth!.treeSize).toBe(1);
+      expect(observed.length).toBe(1);
+
+      // Sanity: server-side latest STH matches what client observed
+      const serverSth = await kt.getLatestSTH();
+      expect(Buffer.from(serverSth.rootHash).toString('hex')).toBe(
+        Buffer.from(result.ktSth!.rootHash).toString('hex'),
+      );
+    } finally {
+      handle.stop();
+    }
+  });
+
+  test('observe-strict throws KTVerificationError on missing proof', async () => {
+    // Plain server (no KT)
+    const { createPrekeyServer, MemoryPrekeyStore } = await import('@shade/server');
+    const app = createPrekeyServer({
+      crypto,
+      store: new MemoryPrekeyStore(),
+      disableRateLimit: true,
+    });
+    const port = 20800 + Math.floor(Math.random() * 200);
+    const handle = Bun.serve({ port, fetch: app.fetch });
+    try {
+      const baseUrl = `http://localhost:${port}`;
+
+      const bobStorage = new MemoryStorage();
+      const bobManager = new ShadeSessionManager(crypto, bobStorage);
+      await bobManager.initialize();
+      const bobIdentity = await bobStorage.getIdentityKeyPair();
+      const bobTransport = new ShadeFetchTransport({
+        baseUrl,
+        crypto,
+        signingPrivateKey: bobIdentity!.signingPrivateKey,
+      });
+      const bobOTPKs = await bobManager.generateOneTimePreKeys(2);
+      const bobBundle = await bobManager.createPreKeyBundle();
+      await bobTransport.register('bob', bobManager.getPublicIdentity(), bobBundle.signedPreKey, bobOTPKs);
+
+      const logKp = await crypto.generateEd25519KeyPair();
+      const aliceTransport = new ShadeFetchTransport({
+        baseUrl,
+        crypto,
+        keyTransparency: { mode: 'observe-strict', logPublicKey: logKp.publicKey },
+      });
+      await expect(aliceTransport.fetchBundle('bob')).rejects.toBeInstanceOf(KTVerificationError);
+    } finally {
+      handle.stop();
+    }
+  });
+
+  test('forged STH (server signed with wrong key) is rejected', async () => {
+    const realLogKp = await crypto.generateEd25519KeyPair();
+    const evilLogKp = await crypto.generateEd25519KeyPair();
+    const { app } = await createPrekeyServerWithKT({
+      crypto,
+      store: new MemoryPrekeyStore(),
+      disableRateLimit: true,
+      keyTransparency: {
+        store: new MemoryKTLogStore(),
+        // Operator signs with the EVIL key
+        signingPrivateKey: evilLogKp.privateKey,
+        signingPublicKey: evilLogKp.publicKey,
+      },
+    });
+    const port = 21100 + Math.floor(Math.random() * 200);
+    const handle = Bun.serve({ port, fetch: app.fetch });
+    try {
+      const baseUrl = `http://localhost:${port}`;
+
+      const bobStorage = new MemoryStorage();
+      const bobManager = new ShadeSessionManager(crypto, bobStorage);
+      await bobManager.initialize();
+      const bobIdentity = await bobStorage.getIdentityKeyPair();
+      const bobTransport = new ShadeFetchTransport({
+        baseUrl,
+        crypto,
+        signingPrivateKey: bobIdentity!.signingPrivateKey,
+      });
+      const bobOTPKs = await bobManager.generateOneTimePreKeys(2);
+      const bobBundle = await bobManager.createPreKeyBundle();
+      await bobTransport.register('bob', bobManager.getPublicIdentity(), bobBundle.signedPreKey, bobOTPKs);
+
+      // Client pinned the REAL log key — verification must fail
+      const aliceTransport = new ShadeFetchTransport({
+        baseUrl,
+        crypto,
+        keyTransparency: { mode: 'observe-strict', logPublicKey: realLogKp.publicKey },
+      });
+      await expect(aliceTransport.fetchBundle('bob')).rejects.toThrow();
+    } finally {
+      handle.stop();
+    }
+  });
+
+  test('observed STH feeds LightWitness; subsequent split-view detected', async () => {
+    const logKp = await crypto.generateEd25519KeyPair();
+    const { app, kt } = await createPrekeyServerWithKT({
+      crypto,
+      store: new MemoryPrekeyStore(),
+      disableRateLimit: true,
+      keyTransparency: {
+        store: new MemoryKTLogStore(),
+        signingPrivateKey: logKp.privateKey,
+        signingPublicKey: logKp.publicKey,
+      },
+    });
+    const port = 21500 + Math.floor(Math.random() * 200);
+    const handle = Bun.serve({ port, fetch: app.fetch });
+    try {
+      const baseUrl = `http://localhost:${port}`;
+
+      // Register Bob
+      const bobStorage = new MemoryStorage();
+      const bobManager = new ShadeSessionManager(crypto, bobStorage);
+      await bobManager.initialize();
+      const bobIdentity = await bobStorage.getIdentityKeyPair();
+      const bobTransport = new ShadeFetchTransport({
+        baseUrl,
+        crypto,
+        signingPrivateKey: bobIdentity!.signingPrivateKey,
+      });
+      const bobOTPKs = await bobManager.generateOneTimePreKeys(2);
+      const bobBundle = await bobManager.createPreKeyBundle();
+      await bobTransport.register('bob', bobManager.getPublicIdentity(), bobBundle.signedPreKey, bobOTPKs);
+
+      // Witness backed by the real /v1/kt/* endpoints
+      const witness = new LightWitness({
+        crypto,
+        logPublicKey: logKp.publicKey,
+        fetcher: {
+          async fetchLatestSTH() {
+            const res = await fetch(`${baseUrl}/v1/kt/sth`);
+            return res.json();
+          },
+          async fetchConsistencyProof(from, to) {
+            const res = await fetch(`${baseUrl}/v1/kt/consistency?from=${from}&to=${to}`);
+            return res.json();
+          },
+        },
+      });
+      const observedSth = await witness.pollOnce();
+      expect(observedSth.treeSize).toBe(1);
+
+      // Forge a divergent STH at the same tree_size and feed it to the
+      // witness (this simulates a malicious second view)
+      const realSth = await kt.getLatestSTH();
+      const tampered = new Uint8Array(realSth.rootHash);
+      tampered[0] ^= 0xff;
+      const forged = await signSth(crypto, logKp.privateKey, {
+        treeSize: realSth.treeSize,
+        timestampMs: realSth.timestampMs,
+        rootHash: tampered,
+        indexRoot: realSth.indexRoot,
+        logId: computeLogId(logKp.publicKey),
+      });
+      await expect(witness.observe(forged)).rejects.toThrow(/Split view/);
+    } finally {
+      handle.stop();
+    }
+  });
+});