chore(main): release 2.1.3

[release-please]

🤖 I have created a release beep boop

2.1.3 (2026-09-15)

Features

• Add psc_endpoint parameter to Sandboxes.send_command and Sandboxes.generate_browser_ws_headers so VPC-SC sandboxes with ingressControlConfig.enablePrivateServiceConnect=true (which populate only connection_info.service_attachment, never load_balancer_hostname / load_balancer_ip) can route data-plane traffic through a customer-provisioned PSC endpoint. Existing non-VPC-SC callers are unaffected; the parameter defaults to None and the load-balancer branches remain the primary path. (39971ae)
• Add build configuration support to Vertex AI Reasoning Engine (bea1abd)
• Add enable_zero_data_retention to Tool.ParallelAiSearch (bea1abd)
• Add enable_zero_data_retention to Tool.ParallelAiSearch (bea1abd)

Bug Fixes

• Fail open on any error resolving the project ID in the ADK templates. (30bf665)
• Fix Sandboxes.send_command failing to reach the sandbox data plane. (2b28caf)
• Import pandas lazily in the Gen AI SDK _gcs_utils module. (7c94277), refs #5928 #7129

Miscellaneous Chores

• Release 2.1.3 (2c7a22d)

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[release-please]

🤖 Created releases:

• v2.1.3

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