fix(tui): separate thinking header from markdown body (#29028)

packages/opencode/test/cli/tui/thinking.test.ts

@@ -0,0 +1,36 @@
+import { describe, expect, test } from "bun:test"
+import { reasoningSummary } from "../../../src/cli/cmd/tui/context/thinking"
+
+describe("reasoningSummary", () => {
+  test("extracts a leading summary title and leaves markdown body", () => {
+    expect(reasoningSummary("**Continuing Quality Review**\n\nDetails.\n\n**Next section**\n\nMore.")).toEqual({
+      title: "Continuing Quality Review",
+      body: "Details.\n\n**Next section**\n\nMore.",
+    })
+  })
+
+  test("extracts a completed title before its streamed body arrives", () => {
+    expect(reasoningSummary("**Continuing Quality Review**")).toEqual({
+      title: "Continuing Quality Review",
+      body: "",
+    })
+  })
+
+  test("preserves markdown-significant indentation in the extracted body", () => {
+    expect(reasoningSummary("**Continuing Quality Review**\n\n    const value = true\n")).toEqual({
+      title: "Continuing Quality Review",
+      body: "    const value = true",
+    })
+  })
+
+  test("does not consume ordinary leading bold content", () => {
+    expect(reasoningSummary("**Important:** keep this in the body.")).toEqual({
+      title: null,
+      body: "**Important:** keep this in the body.",
+    })
+  })
+
+  test("leaves content without a leading title in its body", () => {
+    expect(reasoningSummary("Details only.")).toEqual({ title: null, body: "Details only." })
+  })
+})