[rekram1-node]

Summary

• preserve provider HTTP status on durable session errors and generated clients
• classify payload-size failures separately from model context overflow
• retain both cases as invalid-request subtypes without adding retry behavior

Testing

• bun test test/provider-error.test.ts test/executor.test.ts from packages/ai
• bun test test/session-error.test.ts from packages/core
• bun run generate from packages/client

Typecheck

• package typechecks are blocked by the existing missing @standard-schema/spec dependency