Align retry safety for mutating connector operations across SDKs

Start in ConnectorHttpClient._send_with_retry and ConnectorClientOptions, then inspect the existing retry tests and the shared runtime/options surface used by generated clients. Add focused coverage for safe and unsafe methods, including the opt-in path, and update the API documentation and release notes so the default and opt-in behavior are documented.

Description

Align the Python Connector SDK's retry safety contract with the Node.js SDK behavior introduced in Azure/Connectors-NodeJS-SDK PR #91.

At main commit d273862108d16615009572d730c12950be040a8c, ConnectorHttpClient._send_with_retry retries every HTTP method for 429, every 5xx response, and aiohttp.ClientError. ConnectorClientOptions exposes retry counts and backoff settings but has no method-safety setting. A POST, PUT, PATCH, or DELETE connector action can therefore be submitted again after the service committed it but returned a transient response, or after an ambiguous transport failure.

The cross-language Connector SDK contract should be:

• Retry safe methods (GET, HEAD, OPTIONS, and TRACE) according to the configured retry policy.
• Do not automatically retry unsafe methods (POST, PUT, PATCH, and DELETE) by default.
• Provide an explicit, language-idiomatic per-client opt-in for applying the configured retry policy to unsafe methods, equivalent to Node.js retryUnsafeHttpMethods.
• Preserve the current retry-count, delay, timeout, and exponential-backoff options.

Motivation

Connector operations include side-effecting actions such as sending messages and creating meetings, chats, channels, or files. Automatically replaying a completed action can duplicate customer-visible effects. This risk and the desired explicit opt-in are protocol-level concerns, not Node.js-specific behavior.

Consistent defaults across the .NET, Python, and Node.js Connector SDKs make client behavior predictable when customers move the same connector integration between languages.

Acceptance criteria

• Add a ConnectorClientOptions setting with Python-idiomatic naming for opting unsafe HTTP methods into retries.
• Safe methods retain the configured retry behavior by default.
• Unsafe methods make one attempt by default for both transient HTTP responses and aiohttp.ClientError failures.
• Unsafe methods use the configured retry behavior when explicitly enabled.
• Add focused tests proving at least:
  • a transient GET is retried;
  • a transient POST is sent once by default;
  • a transient POST is retried when explicitly enabled;
  • PUT, PATCH, and DELETE follow the unsafe classification.
• Document the default and opt-in behavior in API documentation and release notes.
• Confirm whether implementation is confined to hand-written runtime/options code. Generated-client regeneration is not expected because generated clients use the shared ConnectorHttpClient and ConnectorClientOptions runtime surface.

Related work

• Node.js implementation: Azure/Connectors-NodeJS-SDK PR #91
• .NET alignment: Azure/Connectors-NET-SDK issue #269