feat(grpc): add v3 SyncKeys

Author: PromiseFru

README.md

@@ -175,10 +175,7 @@ Supported platforms can be retrieved via the REST API: [/v1/platforms](https://p
 - [Installation Guide](INSTALL.md) - Detailed setup instructions
 - [gRPC API](docs/grpc.md) - gRPC interface documentation
 - [REST API](docs/rest.md) - REST API reference
-- [Content Specifications](docs/specification.md) - Payload format specs
-- [REST API (Swagger)](https://publisher.smswithoutborders.com/docs) - Interactive API reference
 - [Platform Adapters](platforms/README.md) - Extending functionality
-- [Reliability Testing](docs/reliability_test.md) - Testing guidelines
 
 ## Testing
 

docs/dfd/adapters_architecture.md

@@ -11,6 +11,7 @@
   - [v3: Get PNBA Code](#v3-get-pnba-code)
   - [v3: Exchange PNBA Code and Store Token](#v3-exchange-pnba-code-and-store-token)
   - [v3: Revoke and Delete PNBA Token](#v3-revoke-and-delete-pnba-token)
+  - [v3: Sync Keys](#v3-sync-keys)
 - [Version 2 API](#version-2-api)
   - [v2: Get OAuth2 Authorization URL](#v2-get-oauth2-authorization-url)
   - [v2: Exchange OAuth2 Code and Store Token](#v2-exchange-oauth2-code-and-store-token)
@@ -392,6 +393,52 @@ grpcurl -plaintext \
 
 ---
 
+### v3: Sync Keys
+
+Syncs the client and server ephemeral key pools for a token. It rotates the client's key pool with a new set of 256 client ephemeral public keys, and the server generates a new pool of 256 server ephemeral keys.
+
+**Request:** `SyncKeysRequest`
+
+| Field | Type | Required | Description |
+| :--- | :--- | :--- | :--- |
+| token_id | bytes | Yes | Unique identifier for the stored token |
+| key_id | uint32 | Yes | The current key index used for encrypting the token |
+| client_ephemeral_public_keys | list[PublicKey] | Yes | Exactly 256 new ephemeral public keys generated by the client |
+
+**Response:** `SyncKeysResponse`
+
+| Field | Type | Description |
+| :--- | :--- | :--- |
+| success | bool | Operation success |
+| message | string | Response message |
+| server_ephemeral_public_keys | list[PublicKey] | Exactly 256 ephemeral public keys generated by the server |
+
+**Example:**
+
+```bash
+grpcurl -plaintext \
+  -H 'x-payload-bin: <encrypted_payload_binary>' \
+  -H 'x-public-key-bin: <client_pk_binary>' \
+  -H 'x-key-id: <key_id>' \
+  -H 'x-nonce-bin: <nonce_binary>' \
+  -H 'x-timestamp: <timestamp>' \
+  -d @ \
+  -proto protos/v3/publisher.proto \
+  <your_host>:<your_port> publisher.v3.Publisher/SyncKeys <<EOF
+{
+  "token_id": "<token_id_binary>",
+  "key_id": 123,
+  "client_ephemeral_public_keys": [
+    {"key_id": 0, "public_key": "..."},
+    ... 254 more keys ...
+    {"key_id": 255, "public_key": "..."}
+  ]
+}
+EOF
+```
+
+---
+
 ## Version 2 API
 
 **Package:** `publisher.v2`