fix(dashboard): honor forced GraphQL transport (#2353)

## Summary
- honor `forceMode` for GraphQL queries and mutations
- keep token-backed Discussion operations on the selected token
transport even when `gh` is authenticated
- add regression coverage for forced-token category lookup, errors, and
Discussion creation

## Test plan
- `CI=true pnpm --filter @fusion/dashboard exec vitest run
src/__tests__/github-discussions.test.ts
src/__tests__/github-forced-mode.test.ts
src/__tests__/github-pr-threads.test.ts`
- `CI=true pnpm build`


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Bug Fixes**
* GitHub Discussions GraphQL operations now consistently honor the
selected transport/authentication mode.
* Forced token-based transport correctly applies to discussion queries
and mutations (including discussion creation).
* Missing required authentication is now reported instead of falling
back to an unauthenticated path.
* **Tests**
* Added a test covering discussion creation using forced token-based
GraphQL transport.
* **Release**
  * Shipped as a patch release of the Fusion library.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

.changeset/fix-github-discussions-force-mode.md

@@ -0,0 +1,7 @@
+---
+"@runfusion/fusion": patch
+---
+
+summary: Honor forced GitHub transport selection for GraphQL discussion queries and mutations.
+category: fix
+dev: Keep Discussion GraphQL operations on the explicitly selected token or gh CLI transport.

packages/dashboard/src/__tests__/github-discussions.test.ts

@@ -31,6 +31,23 @@ describe("GitHub Discussions GraphQL transport", () => {
       .rejects.toThrow("Resource not accessible by personal access token");
   });
 
+  it("creates a discussion through the forced token GraphQL transport", async () => {
+    const fetchMock = vi.fn()
+      .mockResolvedValueOnce(new Response(JSON.stringify({
+        data: { repository: { id: "R_1", discussionCategories: { nodes: [{ id: "DC_1" }] } } },
+      }), { status: 200 }))
+      .mockResolvedValueOnce(new Response(JSON.stringify({
+        data: { createDiscussion: { discussion: { id: "D_1", number: 42, url: "https://github.com/Runfusion/Fusion/discussions/42" } } },
+      }), { status: 200 }));
+    vi.stubGlobal("fetch", fetchMock);
+
+    const discussion = await new GitHubClient({ token: "test", forceMode: "token" })
+      .createDiscussion("Runfusion", "Fusion", "Title", "Body", "DC_1");
+
+    expect(discussion).toEqual({ id: "D_1", number: 42, htmlUrl: "https://github.com/Runfusion/Fusion/discussions/42" });
+    expect(fetchMock).toHaveBeenCalledTimes(2);
+    expect(fetchMock.mock.calls.every(([url]) => String(url) === "https://api.github.com/graphql")).toBe(true);
+  });
 
   it("maps disabled Discussions errors from search to a typed signal", async () => {
     vi.stubGlobal("fetch", vi.fn().mockResolvedValue(new Response(JSON.stringify({

packages/dashboard/src/github.ts

@@ -2457,7 +2457,8 @@ export class GitHubClient {
 
   /** Run a read-only GraphQL query (gh CLI when available, else token/REST). */
   private async runGraphqlQuery<T>(query: string, variables: Record<string, string | number | null>): Promise<T | undefined> {
-    if (this.hasGhAuth()) {
+    if (this.forceMode === "gh-cli" || (this.forceMode === undefined && this.hasGhAuth())) {
+      if (this.forceMode === "gh-cli") this.requireGh();
       const args = ["api", "graphql", "-f", `query=${query}`];
       for (const [key, value] of Object.entries(variables)) {
         if (value === null) continue;
@@ -2469,6 +2470,7 @@ export class GitHubClient {
       if (payload.errors?.length) throw new Error(payload.errors[0].message);
       return payload.data;
     }
+    if (this.forceMode === "token") this.requireToken();
     if (this.token) {
       const response = await fetch(`${this.baseUrl}/graphql`, {
         method: "POST",
@@ -2513,7 +2515,8 @@ export class GitHubClient {
   }
 
   private async runGraphqlMutation(query: string, variables: Record<string, string>): Promise<void> {
-    if (this.hasGhAuth()) {
+    if (this.forceMode === "gh-cli" || (this.forceMode === undefined && this.hasGhAuth())) {
+      if (this.forceMode === "gh-cli") this.requireGh();
       const args = ["api", "graphql", "-f", `query=${query}`];
       for (const [key, value] of Object.entries(variables)) {
         args.push("-F", `${key}=${value}`);
@@ -2523,6 +2526,7 @@ export class GitHubClient {
       if (payload.errors?.length) throw new Error(payload.errors[0].message);
       return;
     }
+    if (this.forceMode === "token") this.requireToken();
     if (this.token) {
       const response = await fetch(`${this.baseUrl}/graphql`, {
         method: "POST",