fix(producer): relax exported types

packages/producer/deno.jsonc

···
 {
   "name": "@cistern/producer",
-  "version": "1.0.1",
+  "version": "1.0.2",
   "license": "MIT",
   "exports": {
     ".": "./mod.ts"

packages/producer/types.ts

···
 import type { BaseClientOptions, ClientRequirements } from "@cistern/shared";
-import type { RecordKey, ResourceUri } from "@atcute/lexicons";
+import type { ResourceUri } from "@atcute/lexicons";
 
 /** Credentials and an optional public key, used for deriving `ProducerParams` */
 export interface ProducerOptions extends BaseClientOptions {
   /** An optional record key to a Cistern public key. Assumed to be within the specified user's PDS, and retrieved before instantiation. You can omit this value if you intend to select a public key later */
-  publicKey?: RecordKey;
+  publicKey?: string;
 }
 
 /** Required parameters for constructing a `Producer`. These are automatically created for you in `createProducer` */