fix(opencode): patch empty Gemini replay messages (#30463)

packages/opencode/test/session/llm.test.ts

@@ -1900,7 +1900,10 @@ describe("session.llm.stream", () => {
           model: resolved,
           agent,
           system: ["You are a helpful assistant."],
-          messages: [{ role: "user", content: "Hello" }],
+          messages: [
+            { role: "user", content: "Hello" },
+            { role: "assistant", content: [{ type: "reasoning", text: "" }] },
+          ],
           tools: {},
         })
 
@@ -1911,6 +1914,9 @@ describe("session.llm.stream", () => {
           | undefined
 
         expect(capture.url.pathname).toBe(pathSuffix)
+        expect(body.contents).toEqual([
+          { role: "user", parts: [{ text: "Hello" }] },
+        ])
         expect(config?.temperature).toBe(0.3)
         expect(config?.topP).toBe(0.8)
         expect(config?.maxOutputTokens).toBe(ProviderTransform.maxOutputTokens(resolved))