fix(sisyphus-task): guard client.session.get and update sync mode tests

- Add guard clause to check if client.session.get exists before calling
- Update 4 sync mode tests to properly mock session.get
- Fixes test failures from PR #731 directory inheritance feature

src/tools/sisyphus-task/tools.test.ts

@@ -452,6 +452,7 @@ describe("sisyphus-task", () => {
       
       const mockClient = {
         session: {
+          get: async () => ({ data: { directory: "/project" } }),
           create: async () => ({ data: { id: "ses_sync_error_test" } }),
           prompt: async () => {
             throw new Error("JSON Parse error: Unexpected EOF")
@@ -504,6 +505,7 @@ describe("sisyphus-task", () => {
       
       const mockClient = {
         session: {
+          get: async () => ({ data: { directory: "/project" } }),
           create: async () => ({ data: { id: "ses_sync_success" } }),
           prompt: async () => ({ data: {} }),
           messages: async () => ({
@@ -560,6 +562,7 @@ describe("sisyphus-task", () => {
       
       const mockClient = {
         session: {
+          get: async () => ({ data: { directory: "/project" } }),
           create: async () => ({ data: { id: "ses_agent_notfound" } }),
           prompt: async () => {
             throw new Error("Cannot read property 'name' of undefined agent.name")
@@ -610,6 +613,7 @@ describe("sisyphus-task", () => {
       const mockManager = { launch: async () => ({}) }
       const mockClient = {
         session: {
+          get: async () => ({ data: { directory: "/project" } }),
           create: async () => ({ data: { id: "ses_sync_model" } }),
           prompt: async (input: any) => {
             promptBody = input.body

src/tools/sisyphus-task/tools.ts

@@ -407,9 +407,9 @@ System notifies on completion. Use \`background_output\` with task_id="${task.id
       let syncSessionID: string | undefined
 
       try {
-        const parentSession = await client.session.get({
-          path: { id: ctx.sessionID },
-        }).catch(() => null)
+        const parentSession = client.session.get
+          ? await client.session.get({ path: { id: ctx.sessionID } }).catch(() => null)
+          : null
         const parentDirectory = parentSession?.data?.directory ?? directory
 
         const createResult = await client.session.create({