release(v4.9.0): relay-side encrypted blob primitive + SDK Profile namespace

Ships the Prism FR (encrypted-profile-storage-v4.9.md) as a generic
relay-side encrypted blob primitive: deterministically-located,
AEAD-sealed blobs keyed by a 32-byte slotId derived client-side via
HKDF from the user's master key. Unlocks credential-only bootstrap
of new devices into existing E2EE state — no QR, no physical access.

Server: BlobStore interface + Memory/Sqlite/Postgres impls,
createBlobRoutes for GET/PUT/DELETE /v1/blob/:slotId with TOFU pubkey
auth and If-Match CAS (409/412 semantics). Mounted on the same Hono
app as the inbox; SHADE_BLOB_PG_URL / SHADE_BLOB_DB_PATH /
SHADE_DISABLE_BLOB env-var plumbing in standalone.

SDK: createProfileNamespace high-level wrapper (HKDF derivation,
random-nonce AEAD seal, slotId-bound AAD) + low-level BlobClient.
Cross-platform test vectors in test-vectors/blob-storage.json.

New errors: ConflictError (409), PreconditionFailedError (412).

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

packages/shade-sdk/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@shade/sdk",
-  "version": "4.8.5",
+  "version": "4.9.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
@@ -8,11 +8,13 @@
     "@shade/core": "workspace:*",
     "@shade/crypto-web": "workspace:*",
     "@shade/files": "workspace:*",
+    "@shade/inbox": "workspace:*",
     "@shade/key-transparency": "workspace:*",
     "@shade/observability": "workspace:*",
     "@shade/observer": "workspace:*",
     "@shade/proto": "workspace:*",
     "@shade/server": "workspace:*",
+    "@shade/storage-encrypted": "workspace:*",
     "@shade/storage-sqlite": "workspace:*",
     "@shade/streams": "workspace:*",
     "@shade/transfer": "workspace:*",
@@ -27,6 +29,7 @@
     }
   },
   "devDependencies": {
+    "@shade/inbox-server": "workspace:*",
     "@shade/transport-webrtc": "workspace:*"
   }
 }