fix: harden session lifecycle and align cli.mdx example with claude.json

- destroySession: wrap session/cancel RPC in try/catch so local cleanup
  always succeeds even when the agent is unreachable
- createSession/resumeOrCreateSession: clean up the remote session if
  post-creation config calls (setMode/setModel/setThoughtLevel) fail,
  preventing leaked orphan sessions
- cli.mdx: fix example output to match current claude.json (model name,
  model order, and populated modes)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docs/cli.mdx

@@ -200,13 +200,22 @@ Example output:
       "models": {
         "currentValue": "default",
         "values": [
-          { "value": "default", "name": "Default (recommended)" },
+          { "value": "default", "name": "Default" },
-          { "value": "opus", "name": "Opus" },
           { "value": "sonnet", "name": "Sonnet" },
+          { "value": "opus", "name": "Opus" },
           { "value": "haiku", "name": "Haiku" }
         ]
       },
-      "modes": { "values": [] },
+      "modes": {
+        "currentValue": "default",
+        "values": [
+          { "value": "default", "name": "Default" },
+          { "value": "acceptEdits", "name": "Accept Edits" },
+          { "value": "plan", "name": "Plan" },
+          { "value": "dontAsk", "name": "Don't Ask" },
+          { "value": "bypassPermissions", "name": "Bypass Permissions" }
+        ]
+      },
       "thoughtLevels": { "values": [] }
     }
   ]

sdks/typescript/src/client.ts

@@ -679,6 +679,7 @@ export class SandboxAgent {
     live.bindSession(record.id, record.agentSessionId);
     let session = this.upsertSessionHandle(record);
 
+    try {
       if (request.mode) {
         session = (await this.setSessionMode(session.id, request.mode)).session;
       }
@@ -688,6 +689,14 @@ export class SandboxAgent {
       if (request.thoughtLevel) {
         session = (await this.setSessionThoughtLevel(session.id, request.thoughtLevel)).session;
       }
+    } catch (err) {
+      try {
+        await this.destroySession(session.id);
+      } catch {
+        // Best-effort cleanup
+      }
+      throw err;
+    }
 
     return session;
   }
@@ -728,6 +737,7 @@ export class SandboxAgent {
     const existing = await this.persist.getSession(request.id);
     if (existing) {
       let session = await this.resumeSession(existing.id);
+      try {
         if (request.mode) {
           session = (await this.setSessionMode(session.id, request.mode)).session;
         }
@@ -737,13 +747,25 @@ export class SandboxAgent {
         if (request.thoughtLevel) {
           session = (await this.setSessionThoughtLevel(session.id, request.thoughtLevel)).session;
         }
+      } catch (err) {
+        try {
+          await this.destroySession(session.id);
+        } catch {
+          // Best-effort cleanup
+        }
+        throw err;
+      }
       return session;
     }
     return this.createSession(request);
   }
 
   async destroySession(id: string): Promise<Session> {
+    try {
       await this.sendSessionMethodInternal(id, SESSION_CANCEL_METHOD, {}, {}, true);
+    } catch {
+      // Best-effort: agent may already be gone
+    }
     const existing = await this.requireSessionRecord(id);
 
     const updated: SessionRecord = {