aws-cpp-sdk-s3-crt: raise error when failing to write download data

[grrtrr]

Currently the S3CrtClient neither logs nor raises an error when failing to write download data.

To avoid the problem of silent failure, check the failbit/badbit after the calls to write() and flush().
Raise and log the error cause.
Return AWS_OP_ERR to mark the download as failed.

Resolves #3824.

Tested on Linux/ubuntu 22.04.

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[grrtrr]

Log output after applying this patch

With my failing download and this patch, I am now seeing this in the logs:

[ERROR] 2026-05-08 19:54:41.884 S3CrtClient [139836522079808] Failed to write download data
[ERROR] 2026-05-08 19:54:41.884 S3MetaRequest [139836522079808] id=0x7f2e44c62400 Response body callback raised error 59 (Failed writing to file.).