feat(sites): add first sites protobuf definition

proto/sites/sites.proto

@@ -0,0 +1,86 @@
+service Sites {
+	// Creates a new site registry based on a hostname provided
+  rpc AddSite(AddSiteRequest) returns (Site);
+
+  // Deletes a site by its ID.
+  rpc RemoveSite(RemoveSiteRequest) returns (google.protobuf.Empty);
+
+  // Gets a single site if exists.
+  rpc GetSite(GetSiteRequest) returns (Site);
+
+  // Updates a site using granular update operations.
+  rpc UpdateSite(UpdateSiteRequest) returns (Site);
+
+  // List currently stored sites a particular user have writes access
+  rpc ListSites(ListSitesRequest) returns (ListSitesResponse);
+}
+
+// the request receives both the hostname and the invite separate,
+// but the UI can decide if we receive a full URL or separate (parse the url in JS)
+message AddSiteRequest {
+
+	// the site host name 
+	string site_hostname = 1;
+
+	// Optional. the invite code generated by the site owner
+	string site_invite = 2;
+}
+
+// possible errors:
+//   - the host name is invalid (no mintter server)
+//	 - the invite code is invalid
+//	 - you are a nobody (NONE role)
+
+message Site {
+  // the site host name. it must be unique, so it's safe to use it as the Site ID
+  string hostname = 1;
+
+	// the role of the user in the current site
+	Role role = 2;
+
+	// the public title of a Site
+	string title = 3;
+
+	// the site's public description
+	string description = 4;
+
+	// the editor's account id list. I was thinking on adding a separate list and separate rpc method, but for now it does not really matter much!
+	repeated string editors = 5;
+}
+
+enum Role {
+	OWNER = 0,
+	EDITOR = 1,
+	NONE = 2
+}
+
+message RemoveSiteRequest {
+
+	// the side id you want to remove from the local node
+	string site_hostname = 1;
+}
+
+message GetSiteRequest {
+
+	// the side id you want to get from the local node
+	string site_hostname = 1;
+}
+
+message UpdateSiteRequest {
+
+	string site_hostname = 1;
+
+	// Optional. the title of a Site
+	string site_title = 2;
+
+	// Optional. the site's description
+	string site_description = 3;
+}
+
+// Response for listing sites.
+message ListSitesResponse {
+  // Sites matching the list request.
+  // Editors is omitted.
+  repeated Site sites = 1;
+
+}