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## 2.13.0

**`(feat):`** Auto-generation of the idempotency key header is now driven by the IR
(`sdkConfig.idempotencyKeyGeneration`) instead of a generator config flag. When
enabled, retry-unsafe requests (the IR-configured eligible methods, POST/PUT by
default) attach the configured header (default `Idempotency-Key`) with a freshly
generated UUIDv4 unless the caller supplies one. The header name and eligible
methods come from the IR so behavior is consistent across generators.

## 2.12.0

**`(feat):`** Add support for server URL variables (e.g. region/edge routing). Server variables
defined on the API's environments are now exposed as optional string parameters on
the client constructor and interpolated into the base URL(s) at construction time,
falling back to each variable's default when not provided. Conflicting constructor
option names are de-collided with a `serverUrl` prefix and numeric suffix when needed
(e.g. a variable named `environment` is exposed as `serverUrlEnvironment`).