[438] Stdout/stderr streaming to blob storage

[giventocode]

Closes: #438

In this PR:

• The standard output and error streams are redirected and sent to blob storage.
  • Each operation (download, executor, upload) generates log files for both standard output and error streams.
  • Data is written in blocks of 16KiB to an append blob.
• Executor (the process that runs commands on the container) is launched as a separate process to enable consistent log streaming for all operations.
  • The CLI has a new command: exec.
  • The root command runs all commands/operations as sub-processes.
• Logging format is changed. The log format is now simple instead of systemd.
• Renamed 'BlockBlobApiHttpUtils' to 'BlobApiHttpUtils'