MINIFICPP-2705 - Configurable timeout, download assets directly to disk

[adamdebreceni]

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[Copilot]

Pull request overview

This PR implements configurable timeout for asset downloads and changes the download mechanism to stream data directly to disk rather than loading it entirely in memory first. This improves memory efficiency for large asset downloads.

Changes:

• Added new configuration property nifi.c2.asset.download.timeout for controlling asset download timeouts
• Refactored HTTP read callback architecture to support streaming chunk-based processing
• Modified asset and flow download implementations to write directly to disk/strings via chunk callbacks

Reviewed changes

Copilot reviewed 16 out of 16 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
minifi-api/include/minifi-cpp/properties/Configuration.h	Added new configuration constant for asset download timeout
libminifi/include/c2/C2Protocol.h	Changed fetch interface to accept chunk callback instead of returning payload
libminifi/include/c2/protocols/RESTSender.h	Added asset_download_timeout member and updated fetch signature
libminifi/include/utils/file/AssetManager.h	Updated sync method signature to accept callback that writes to file path
libminifi/src/c2/C2Agent.cpp	Implemented streaming download for assets and flows using chunk callbacks
libminifi/src/c2/protocols/RESTSender.cpp	Implemented new fetch method with timeout support and chunk-based processing
libminifi/src/utils/file/AssetManager.cpp	Updated to use fetch callback that writes directly to disk
core-framework/include/http/BaseHTTPClient.h	Refactored HTTPReadCallback hierarchy for chunk-based processing
core-framework/include/http/HTTPClient.h	Added setAbsoluteTimeout method and absolute_timeout member
core-framework/include/http/HTTPStream.h	Updated to use dynamic_cast for ByteOutputCallback access
core-framework/include/utils/ByteArrayCallback.h	Changed write methods to accept const char*
core-framework/src/http/BaseHTTPClient.cpp	Updated receiveWrite to use new process method
core-framework/src/http/HTTPClient.cpp	Updated getResponseBody to use dynamic_cast
core-framework/src/http/HTTPStream.cpp	Updated close and read to use dynamic_cast
core-framework/src/utils/ByteArrayCallback.cpp	Updated write methods to accept const char*
C2.md	Added documentation for new timeout configuration property

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[lordgamez]

Minor nitpicks aside LGTM. I was thinking if there could be added tests for these changes, but even just testing the timeout may be more complicated than its worth, so I suppose the current functionality tests should suffice.