RFR: 8319055: JCMD should not buffer the whole output of commands

[Alex Menkov]

The fix implements streaming output support for attach protocol.
See JBS issue for evaluation, summary of the changes in the 1st comment.
Testing: tier1..4,hs-tier5-svc

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Commit messages:
 - jcheck
 - jcheck
 - fix

Changes: https://git.openjdk.org/jdk/pull/23405/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=23405&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8319055
  Stats: 672 lines in 12 files changed: 493 ins; 60 del; 119 mod
  Patch: https://git.openjdk.org/jdk/pull/23405.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23405/head:pull/23405

PR: https://git.openjdk.org/jdk/pull/23405