fix: restore full simulation suite reliability

[hadarishav]

Summary

• restore isolated chat execution by forwarding the configured AgentCC gateway credentials
• preserve safe chat abort markers across the worker boundary
• classify container-shaped contract fields before scalar words in their descriptions
• retry transient usage-service transport and HTTP 5xx failures with a bounded policy
• extend the provider-import example backend to match the current Vapi pharmacy assistant tools

Validation

• 88 focused ALK tests passed
• Ruff formatting, lint, compilation, and diff checks passed
• certified and exercised through E2B using five scenarios per runnable regression lane
• Vapi clone/rewire and Vapi code-created flows completed with transcripts, four audio artifacts per voice call, subgoals, and cleanup
• packaged chat, unpackaged chat, Vertex chat, LiveKit voice, and multi-store chat paths completed end to end

External blockers found during regression

• Retell clone/create requires provider lifecycle permissions; the current key is missing Agent.Write
• the Retell account is payment-blocked for live voice/chat execution
• Alderway joins the LiveKit room but does not produce speech

These are provider or target-agent blockers, not harness failures.

[KarthikAvinashFI]

Ran the changed test files on this merged with dev, all pass. The chat worker, usage retry and AgentCC changes look good. One thing inline on the column-type reorder.

[KarthikAvinashFI]

Checked 2c235a2, the bundle-author tests pass on this head. Thanks for the fix.