fix(agents): include SOUL.md, IDENTITY.md, USER.md in subagent/cron bootstrap allowlist

Subagent and isolated cron sessions only loaded AGENTS.md and TOOLS.md,
causing subagents to lose their role personality, identity, and user
preferences. Expand MINIMAL_BOOTSTRAP_ALLOWLIST to include the three
missing identity files.

Closes #24852

(cherry picked from commit c33377150e)

src/agents/workspace.test.ts

@@ -11,8 +11,10 @@ import {
   DEFAULT_TOOLS_FILENAME,
   DEFAULT_USER_FILENAME,
   ensureAgentWorkspace,
+  filterBootstrapFilesForSession,
   loadWorkspaceBootstrapFiles,
   resolveDefaultAgentWorkspaceDir,
+  type WorkspaceBootstrapFile,
 } from "./workspace.js";
 
 describe("resolveDefaultAgentWorkspaceDir", () => {
@@ -141,3 +143,52 @@ describe("loadWorkspaceBootstrapFiles", () => {
     expect(getMemoryEntries(files)).toHaveLength(0);
   });
 });
+
+describe("filterBootstrapFilesForSession", () => {
+  const mockFiles: WorkspaceBootstrapFile[] = [
+    { name: "AGENTS.md", path: "/w/AGENTS.md", content: "", missing: false },
+    { name: "SOUL.md", path: "/w/SOUL.md", content: "", missing: false },
+    { name: "TOOLS.md", path: "/w/TOOLS.md", content: "", missing: false },
+    { name: "IDENTITY.md", path: "/w/IDENTITY.md", content: "", missing: false },
+    { name: "USER.md", path: "/w/USER.md", content: "", missing: false },
+    { name: "HEARTBEAT.md", path: "/w/HEARTBEAT.md", content: "", missing: false },
+    { name: "BOOTSTRAP.md", path: "/w/BOOTSTRAP.md", content: "", missing: false },
+    { name: "MEMORY.md", path: "/w/MEMORY.md", content: "", missing: false },
+  ];
+
+  it("returns all files for main session (no sessionKey)", () => {
+    const result = filterBootstrapFilesForSession(mockFiles);
+    expect(result).toHaveLength(mockFiles.length);
+  });
+
+  it("returns all files for normal (non-subagent, non-cron) session key", () => {
+    const result = filterBootstrapFilesForSession(mockFiles, "agent:default:chat:main");
+    expect(result).toHaveLength(mockFiles.length);
+  });
+
+  it("filters to allowlist for subagent sessions", () => {
+    const result = filterBootstrapFilesForSession(mockFiles, "agent:default:subagent:task-1");
+    const names = result.map((f) => f.name);
+    expect(names).toContain("AGENTS.md");
+    expect(names).toContain("TOOLS.md");
+    expect(names).toContain("SOUL.md");
+    expect(names).toContain("IDENTITY.md");
+    expect(names).toContain("USER.md");
+    expect(names).not.toContain("HEARTBEAT.md");
+    expect(names).not.toContain("BOOTSTRAP.md");
+    expect(names).not.toContain("MEMORY.md");
+  });
+
+  it("filters to allowlist for cron sessions", () => {
+    const result = filterBootstrapFilesForSession(mockFiles, "agent:default:cron:daily-check");
+    const names = result.map((f) => f.name);
+    expect(names).toContain("AGENTS.md");
+    expect(names).toContain("TOOLS.md");
+    expect(names).toContain("SOUL.md");
+    expect(names).toContain("IDENTITY.md");
+    expect(names).toContain("USER.md");
+    expect(names).not.toContain("HEARTBEAT.md");
+    expect(names).not.toContain("BOOTSTRAP.md");
+    expect(names).not.toContain("MEMORY.md");
+  });
+});

src/agents/workspace.ts

@@ -494,7 +494,13 @@ export async function loadWorkspaceBootstrapFiles(dir: string): Promise<Workspac
   return result;
 }
 
-const MINIMAL_BOOTSTRAP_ALLOWLIST = new Set([DEFAULT_AGENTS_FILENAME, DEFAULT_TOOLS_FILENAME]);
+const MINIMAL_BOOTSTRAP_ALLOWLIST = new Set([
+  DEFAULT_AGENTS_FILENAME,
+  DEFAULT_TOOLS_FILENAME,
+  DEFAULT_SOUL_FILENAME,
+  DEFAULT_IDENTITY_FILENAME,
+  DEFAULT_USER_FILENAME,
+]);
 
 export function filterBootstrapFilesForSession(
   files: WorkspaceBootstrapFile[],

src/hooks/bundled/bootstrap-extra-files/handler.test.ts

@@ -92,7 +92,10 @@ describe("bootstrap-extra-files hook", () => {
 
     const event = createHookEvent("agent", "bootstrap", "agent:main:subagent:abc", context);
     await handler(event);
-
-    expect(context.bootstrapFiles.map((f) => f.name).toSorted()).toEqual(["AGENTS.md", "TOOLS.md"]);
+    expect(context.bootstrapFiles.map((f) => f.name).toSorted()).toEqual([
+      "AGENTS.md",
+      "SOUL.md",
+      "TOOLS.md",
+    ]);
   });
 });