feat(FN-3876): add GitHub tracking test coverage across settings, issues, s

Adds comprehensive test coverage for GitHub tracking across four areas: settings inheritance, issue creation, status sync transitions, and unlink sync regression — spanning 280 lines of new tests across four test files with minimal store.ts adjustment.

Fusion-Task-Id: FN-3876

packages/core/src/__tests__/github-tracking-settings.test.ts

@@ -0,0 +1,101 @@
+import { afterEach, beforeEach, describe, expect, it } from "vitest";
+import { mkdtempSync } from "node:fs";
+import { rm } from "node:fs/promises";
+import { join } from "node:path";
+import { tmpdir } from "node:os";
+
+import { resolveTaskGithubTracking } from "../github-tracking.js";
+import type { TaskGithubTrackedIssue } from "../types.js";
+import { TaskStore } from "../store.js";
+
+function makeTmpDir(): string {
+  return mkdtempSync(join(tmpdir(), "kb-store-github-tracking-settings-test-"));
+}
+
+describe("github tracking settings inheritance", () => {
+  it.each([
+    ["task", { githubTracking: { repoOverride: "task/override" } }, { githubTrackingDefaultRepo: "project/default" }, { githubTrackingDefaultRepo: "global/default" }, "task/override"],
+    ["project", { githubTracking: {} }, { githubTrackingDefaultRepo: "project/default" }, { githubTrackingDefaultRepo: "global/default" }, "project/default"],
+    ["global", { githubTracking: {} }, {}, { githubTrackingDefaultRepo: "global/default" }, "global/default"],
+    ["none", { githubTracking: {} }, {}, {}, null],
+  ] as const)("resolves repo with %s precedence", (_name, task, projectSettings, globalSettings, expectedSlug) => {
+    const resolved = resolveTaskGithubTracking(task as any, projectSettings as any, globalSettings as any);
+    const actual = resolved.repo ? `${resolved.repo.owner}/${resolved.repo.repo}` : null;
+    expect(actual).toBe(expectedSlug);
+  });
+
+  it.each([
+    ["task", { githubTracking: { enabled: true } }, { githubTrackingEnabledByDefault: false }, undefined, true],
+    ["project", { githubTracking: {} }, { githubTrackingEnabledByDefault: true }, undefined, true],
+    ["global", { githubTracking: {} }, {}, { githubTrackingDefaultEnabledForNewTasks: true }, true],
+    ["default", { githubTracking: {} }, {}, undefined, false],
+  ] as const)("resolves enabled with %s precedence", (_name, task, projectSettings, globalSettings, expectedEnabled) => {
+    const resolved = resolveTaskGithubTracking(task as any, projectSettings as any, globalSettings as any);
+    expect(resolved.enabled).toBe(expectedEnabled);
+  });
+});
+
+describe("github tracking task persistence", () => {
+  let rootDir: string;
+  let globalDir: string;
+  let store: TaskStore;
+
+  beforeEach(async () => {
+    rootDir = makeTmpDir();
+    globalDir = makeTmpDir();
+    store = new TaskStore(rootDir, globalDir, { inMemoryDb: true });
+    await store.init();
+  });
+
+  afterEach(async () => {
+    store.close();
+    await rm(rootDir, { recursive: true, force: true });
+    await rm(globalDir, { recursive: true, force: true });
+  });
+
+  it("defaults new tasks to tracking off when no override exists", async () => {
+    const task = await store.createTask({ description: "Default tracking off" });
+    const resolved = resolveTaskGithubTracking(task, { githubTrackingEnabledByDefault: false }, undefined);
+    expect(task.githubTracking).toBeUndefined();
+    expect(resolved.enabled).toBe(false);
+  });
+
+  it("round-trips per-task githubTracking through create, load, and update", async () => {
+    const issue: TaskGithubTrackedIssue = {
+      owner: "octocat",
+      repo: "hello-world",
+      number: 42,
+      url: "https://github.com/octocat/hello-world/issues/42",
+      createdAt: "2026-05-09T00:00:00.000Z",
+    };
+
+    const created = await store.createTask({
+      description: "Track this",
+      githubTracking: {
+        enabled: true,
+        repoOverride: "octocat/hello-world",
+        issue,
+      },
+    });
+
+    const loaded = await store.getTask(created.id);
+    expect(loaded?.githubTracking).toEqual({
+      enabled: true,
+      repoOverride: "octocat/hello-world",
+      issue,
+    });
+
+    await store.updateGithubTracking(created.id, {
+      enabled: false,
+      repoOverride: "octocat/updated-repo",
+      issue,
+    });
+
+    const updated = await store.getTask(created.id);
+    expect(updated?.githubTracking).toEqual({
+      enabled: false,
+      repoOverride: "octocat/updated-repo",
+      issue,
+    });
+  });
+});

packages/core/src/store.ts

@@ -2522,6 +2522,7 @@ export class TaskStore extends EventEmitter<TaskStoreEvents> {
       priority: normalizeTaskPriority(input.priority),
       tokenUsage: input.tokenUsage,
       sourceIssue: input.sourceIssue,
+      githubTracking: input.githubTracking,
       sourceType: input.source?.sourceType ?? "unknown",
       sourceAgentId: input.source?.sourceAgentId,
       sourceRunId: input.source?.sourceRunId,