fix(ai-ollama): forward systemPrompts to Ollama API (#389)

The `mapCommonOptionsToOllama()` method was silently dropping the `systemPrompts` field from chat options. System prompts passed via `chat({ systemPrompts: [...] })` now correctly reach the Ollama API as the `system` parameter on the chat request. This is how other adapters (e.g. Anthropic) handle it.

Author: Spiralis

packages/typescript/ai-ollama/src/adapters/text.ts

@@ -483,6 +483,9 @@ export class OllamaTextAdapter<TModel extends string> extends BaseTextAdapter<
       options: ollamaOptions,
       messages: this.formatMessages(options.messages),
       tools: this.convertToolsToOllamaFormat(options.tools),
+      ...(options.systemPrompts?.length
+        ? { system: options.systemPrompts.join('\n') }
+        : {}),
     }
   }
 }