feat(FN-3913): add GitHub tracking guide section to task-management docs

Adds a new GitHub tracking issues guide section to the task management documentation, with a contract test to validate the docs content.

Fusion-Task-Id: FN-3913

packages/dashboard/src/__tests__/github-tracking-documentation.test.ts

@@ -0,0 +1,41 @@
+// @vitest-environment node
+
+import { describe, it, expect } from "vitest";
+import { readFileSync } from "node:fs";
+import path from "node:path";
+
+const repoRoot = path.resolve(__dirname, "../../../../");
+
+function readDoc(relativePath: string): string {
+  return readFileSync(path.join(repoRoot, relativePath), "utf8");
+}
+
+describe("github tracking documentation contract", () => {
+  it("documents the GitHub Tracking Issues section with required behavior", () => {
+    const taskManagement = readDoc("docs/task-management.md");
+
+    expect(taskManagement).toContain("## GitHub Tracking Issues");
+    expect(taskManagement).toContain("They are **not** the same as imported source issues (`issueInfo` / `sourceIssue`)");
+    expect(taskManagement).toContain("task creation flows (including quick create, planning output, and subtask creation paths that create tasks)");
+    expect(taskManagement).toContain("task.githubTracking.enabled");
+    expect(taskManagement).toContain("task.githubTracking.repoOverride");
+    expect(taskManagement).toContain("Repository resolution order");
+    expect(taskManagement).toContain("1. Task override: `task.githubTracking.repoOverride`");
+    expect(taskManagement).toContain("2. Project default: `githubTrackingDefaultRepo`");
+    expect(taskManagement).toContain("3. Global default: `githubTrackingDefaultRepo`");
+    expect(taskManagement).toContain("Creation is best-effort and non-blocking");
+    expect(taskManagement).toContain("Title: `[FN-XXXX] Task title`");
+    expect(taskManagement).toContain("Body prefix: `Fusion task: FN-XXXX`");
+  });
+
+  it("keeps GitHub auth cross-links discoverable from task management docs", () => {
+    const taskManagement = readDoc("docs/task-management.md");
+    const settingsReference = readDoc("docs/settings-reference.md");
+
+    expect(taskManagement).toContain("[Settings Reference](./settings-reference.md)");
+    expect(taskManagement).toContain("`githubAuthMode` (`gh-cli` or `token`) and `githubAuthToken`");
+
+    expect(settingsReference).toContain("`githubAuthMode` | `\"gh-cli\" \\\| \"token\"` | `\"gh-cli\"`");
+    expect(settingsReference).toContain("`githubAuthToken` | `string` | `undefined`");
+  });
+});