feat(api): add account workspaces and signed content events

test-vectors/vectors.json

@@ -1,5 +1,32 @@
 {
   "version": 1,
+  "signatures": {
+    "x": "OJVV0pkDZHH7F92rxIQt1EuXk4ZesLwoWTaMSANt79A",
+    "y": "HRP3ZgqoD_8Iv42Mw1oflcJUKeq3H1gEbbOLNJoC_zs",
+    "kind": "chat.create",
+    "payload": "01020304deadbeef",
+    "signature": "9dad329614d98c97acc5a60622329e57e111fd7579edc7e4bcc535476aae281cc7e3ee00fa2d5d901af525875af653d74bd441ca5dd54d00081b51b7c3b5adcb",
+    "message": "57445301000b636861742e6372656174650000000801020304deadbeef"
+  },
+  "content_event": {
+    "space_id": "000102030405060708090a0b0c0d0e0f",
+    "channel_id": "01234567-89ab-cdef-0123-456789abcdef",
+    "username": "alice",
+    "device_id": "11111111-2222-3333-4444-555555555555",
+    "event_id": "d0d1d2d3d4d5d6d7d8d9dadbdcdddedf",
+    "kind": "chat.edit",
+    "domain": "chat",
+    "epoch": 2,
+    "item_id": "a0a1a2a3a4a5a6a7a8a9aaabacadaeaf",
+    "frame_count": 2,
+    "target_item_id": "b0b1b2b3b4b5b6b7b8b9babbbcbdbebf",
+    "frame_digests": [
+      "3132333435363738393a3b3c3d3e3f404142434445464748494a4b4c4d4e4f50",
+      "7172737475767778797a7b7c7d7e7f808182838485868788898a8b8c8d8e8f90"
+    ],
+    "manifest_hash": "97c6a9995ae971032e62baa1f2388f966c814d8a2e22c7299715879809d6d98c",
+    "payload": "000102030405060708090a0b0c0d0e0f2430313233343536372d383961622d636465662d303132332d34353637383961626364656605616c6963652431313131313131312d323232322d333333332d343434342d353535353535353535353535d0d1d2d3d4d5d6d7d8d9dadbdcdddedf09636861742e656469740100000002a0a1a2a3a4a5a6a7a8a9aaabacadaeaf0000000297c6a9995ae971032e62baa1f2388f966c814d8a2e22c7299715879809d6d98c01b0b1b2b3b4b5b6b7b8b9babbbcbdbebf"
+  },
   "inputs": {
     "channel_id": "000102030405060708090a0b0c0d0e0f",
     "channel_id_b64": "AAECAwQFBgcICQoLDA0ODw",