Lead the digest with busy time and take its idle patterns in correlate - #30

Summary

The digest (jonoffcpu-summary.md / .json) wasn't useful on its own:

• Busy and idle were ranked side by side, and the idle table listed waits nobody needs.
• Idle waits were known only through preset:jvm-idle, so an application's own idle waits landed in the busy tables. On an Apache Pulsar broker capture, 87 % of the digest's "busy" time was BookKeeper workers waiting for a task (GrowableBatchedArrayBlockingQueue.takeAll).

This PR makes the digest the idle-filtered summary.

• correlate --idle REGEX / --idle-from FILE (default preset:jvm-idle) set the idle patterns for the digest alone.
  • The collapsed stacks, the profile and the report keep every interval.
  • The patterns are resolved before correlating, so a bad pattern fails at once.
  • Two combinations are rejected: these options with --summary-output false, and these options in partial mode.
• The digest is busy-first:
  • "Where the time went" leads with Busy, then "Idle, left out below" and All selected, and keeps the over-exclusion check.
  • A note under that table says the tables and stacks below cover busy time only, names the idle patterns, and gives the top command that lists the idle waits.
  • The busy tables and the heaviest stacks (now titled "Heaviest busy stacks") leave idle intervals out, as before.
  • The idle table is gone.
• summarize writes the same layout, and its help and the shared --idle description say what idle now means for the digest.

On that broker capture, with --idle-from pointing at the harness's idle list (the preset plus BookKeeper's …BlockingQueue.take(All)), busy time comes to 43.371 s. That matches the harness's own idle-filtered flame graph, and the busy table now ranks thread start, monitor and lock contention.

Compatibility

• jonoffcpu-summary.json: Digest.idle (field 10) is removed and reserved. The idle totals remain in whereTheTimeWent.
• Markdown: "Where the time went" rows are reordered. There's no idle section, and the heaviest stacks section is renamed.

Verification

• ./gradlew spotlessCheck :jonoffcpu-agent:check :jonoffcpu-correlator:check :jonoffcpu-jfr-converter:check :jonoffcpu-capture-codec:check passes: 302 tests, 0 failures.
• New assertions check four things:
  • correlate --idle-from with a pattern matching every frame leaves no busy time in the digest.
  • It leaves the collapsed stacks and the profile byte-identical.
  • The digest names the pattern file.
  • --idle is rejected with --summary-output false and in partial mode.
• The digest test checks the busy-first layout, and that the default preset's idle interval stays out of the busy table.
• Help snapshots for correlate, summarize, top and the root command are regenerated. The README option table is checked by readmeTest.