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>

test-vectors/streams.json

@@ -0,0 +1,105 @@
+{
+  "version": 2,
+  "vectors": [
+    {
+      "description": "deriveStreamKey: HKDF(streamSecret, salt=streamId, info=\"shade-stream/v1\\0master\")",
+      "streamSecret": "a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1",
+      "streamId": "b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2",
+      "streamKey": "2eb635cee7797336215657bd84a60238b49053d7fd1a2696b4cb18046b6dfbf5"
+    },
+    {
+      "description": "deriveLaneKey: HKDF(streamKey, salt=streamId, info=\"shade-stream/v1\\0lane\\0\" || u32_be(laneId))",
+      "streamKey": "2eb635cee7797336215657bd84a60238b49053d7fd1a2696b4cb18046b6dfbf5",
+      "streamId": "b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2",
+      "lanes": [
+        {
+          "laneId": 0,
+          "laneKey": "0849f549230b1522e00fa50199bd336cbccd896293a6d42e9fced63665a471f0"
+        },
+        {
+          "laneId": 1,
+          "laneKey": "74d4b6384626b751581c94f589c34846f67b5e198b12960c45da147d2913fa0b"
+        },
+        {
+          "laneId": 2,
+          "laneKey": "cad987dbb6b8b72b13ad125116e6de6c3c39f2f38bca522fb7d129fb1ab38860"
+        },
+        {
+          "laneId": 4294967295,
+          "laneKey": "f88038166f595cfcd85d47b5a05038ea00e097768ff8a0e8f6eaad8651e62163"
+        }
+      ]
+    },
+    {
+      "description": "buildChunkNonce(laneId, seq): u32_be(laneId) || u64_be(seq)",
+      "nonces": [
+        {
+          "laneId": 0,
+          "seq": "0",
+          "nonce": "000000000000000000000000"
+        },
+        {
+          "laneId": 0,
+          "seq": "1",
+          "nonce": "000000000000000000000001"
+        },
+        {
+          "laneId": 1,
+          "seq": "0",
+          "nonce": "000000010000000000000000"
+        },
+        {
+          "laneId": 4294967295,
+          "seq": "18446744073709551614",
+          "nonce": "fffffffffffffffffffffffe"
+        }
+      ]
+    },
+    {
+      "description": "buildChunkAad(streamId, laneId, seq, isLast): streamId(16) || u32_be(laneId) || u64_be(seq) || u8(isLast)",
+      "streamId": "b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2",
+      "cases": [
+        {
+          "laneId": 0,
+          "seq": "0",
+          "isLast": false,
+          "aad": "b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b200000000000000000000000000"
+        },
+        {
+          "laneId": 1,
+          "seq": "7",
+          "isLast": true,
+          "aad": "b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b200000001000000000000000701"
+        },
+        {
+          "laneId": 4294967295,
+          "seq": "18446744073709551614",
+          "isLast": false,
+          "aad": "b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2fffffffffffffffffffffffe00"
+        }
+      ]
+    },
+    {
+      "description": "End-to-end chunk encrypt: AES-256-GCM(laneKey, nonce, plaintext, aad)",
+      "laneId": 0,
+      "seq": "0",
+      "isLast": true,
+      "laneKey": "0849f549230b1522e00fa50199bd336cbccd896293a6d42e9fced63665a471f0",
+      "nonce": "000000000000000000000000",
+      "aad": "b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b200000000000000000000000001",
+      "plaintext": "53686164652073747265616d732030783131206368756e6b20766563746f72",
+      "ciphertext": "060928337f09ea3d6b979b00d6db008f0f0f885b72684b9042ec3368c55fb9fdd7ee2b94f3f4c08061c12bbc3607c8"
+    },
+    {
+      "description": "Wire 0x11 stream-chunk envelope encode/decode",
+      "streamId": "b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2",
+      "laneId": 0,
+      "seq": "0",
+      "isLast": true,
+      "nonce": "000000000000000000000000",
+      "extraAad": "",
+      "ciphertext": "060928337f09ea3d6b979b00d6db008f0f0f885b72684b9042ec3368c55fb9fdd7ee2b94f3f4c08061c12bbc3607c8",
+      "encoded": "0211b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b200000000000000000000000001000000000000000000000000000000000000002f060928337f09ea3d6b979b00d6db008f0f0f885b72684b9042ec3368c55fb9fdd7ee2b94f3f4c08061c12bbc3607c8"
+    }
+  ]
+}