Improve Foundry auth and task flows (#240)

foundry/packages/backend/src/services/github-auth.ts

@@ -0,0 +1,30 @@
+import { getOrCreateWorkspace } from "../actors/handles.js";
+import { APP_SHELL_WORKSPACE_ID } from "../actors/workspace/app-shell.js";
+
+export interface ResolvedGithubAuth {
+  githubToken: string;
+  scopes: string[];
+}
+
+export async function resolveWorkspaceGithubAuth(c: any, workspaceId: string): Promise<ResolvedGithubAuth | null> {
+  if (!workspaceId || workspaceId === APP_SHELL_WORKSPACE_ID) {
+    return null;
+  }
+
+  try {
+    const appWorkspace = await getOrCreateWorkspace(c, APP_SHELL_WORKSPACE_ID);
+    const resolved = await appWorkspace.resolveAppGithubToken({
+      organizationId: workspaceId,
+      requireRepoScope: true,
+    });
+    if (!resolved?.accessToken) {
+      return null;
+    }
+    return {
+      githubToken: resolved.accessToken,
+      scopes: Array.isArray(resolved.scopes) ? resolved.scopes : [],
+    };
+  } catch {
+    return null;
+  }
+}