NIFI-15139 Fix bootstrap diagnostics argument handling

[exceptionfactory]

Summary

NIFI-15139 Corrects argument handling for the diagnostics command of the bootstrap process to support both the verbose and the output path arguments together in either order.

The initial refactored bootstrap implementation worked with the output path specified, but did not handle the verbose option correctly.

The refactored approach delegates argument processing to a separate DiagnosticsBootstrapCommandProvider and introduces a new unit test that exercises command execution, confirming the URI requested and the presence of the diagnostics output file when requested.

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  • JDK 21
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