[JENKINS-72009, JENKINS-72200, JENKINS-24947] various fixes and improvements around disk space monitoring

[mawinter69]

JENKINS-24947:

• Introduce a NodeProperty to define agent specific thresholds for free disk and temp space.

JENKINS-72009

• Enhance the tooltip in the executor widget so it includes the threshold (also fixes a wrong conversion)
• Show a tooltip in the nodes table when agent was marked offline or has a warning about low diskspace
• Use binary prefixes when showing the disk space (GB -> GiB)
• allow to configure also a warning level
• Change text of configure button to make it clearer what it does
• Store totalsize to so we can show it in tooltips
• Show a tooltip also when all is good that contains total size and the path

JENKINS-72200:

• ensure an agent is taken offline/online due to diskspace when the background nodemonitor runs.

an admin monitor for disk space warnings is very hard to implement, so skipping for now

support-core and metrics plugin should be adjusted to reflect agent individual thresholds.

See JENKINS-72009
JENKINS-72200
JENKINS-24947

Testing done

• Manual testing as described in JENKINS-72200
• Configure node properties for agents and verify they are taken offline or show a warning

Proposed changelog entries

• Allow configuration of disk thresholds globally and for each agent. Improve warning when disk space is too low. Ensure agents are taken offline when disk space is low.

Proposed upgrade guidelines

N/A

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[comment-ops-bot]

I wasn't able to add the following labels: needs-more-review

Check that the label exists and is spelt right then try again.

[abhishekmaity]

/label needs-more-reviews

[abhishekmaity]

@jenkinsci/core-pr-reviewers

[Kevin-CB]

Looks fine from a security perspective

[Kevin-CB]

This is not accurate anymore, it will never return HTML

[MarkEWaite]

I really like the direction this is moving very much. Interactive testing found no issues. Thanks!

[MarkEWaite]

Interactive testing showed that all the settings worked very well. I confirmed that the settings are visible through configuration as code and that agents are taken offline when the thresholds are exceeded.

[MarkEWaite]

Thanks very much!

[timja]

/label ready-for-merge

---

This PR is now ready for merge, after ~24 hours, we will merge it if there's no negative feedback.

Thanks!

[jglick]

Note: this is one of the unusual cases where a settings format change is not forward-compatible. So if you run a controller from a version after this PR and then downgrade to a version prior to it and try to save monitor config, you will get an error

java.lang.NumberFormatException: For input string: "1GI"
	at java.base/jdk.internal.math.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:2054)
	at java.base/jdk.internal.math.FloatingDecimal.parseDouble(FloatingDecimal.java:110)
	at java.base/java.lang.Double.parseDouble(Double.java:792)
	at hudson.node_monitors.DiskSpaceMonitorDescriptor$DiskSpace.parse(DiskSpaceMonitorDescriptor.java:163)
	at hudson.node_monitors.AbstractDiskSpaceMonitor.<init>(AbstractDiskSpaceMonitor.java:23)
	at hudson.node_monitors.DiskSpaceMonitor.<init>(DiskSpaceMonitor.java:49)
	at …
Caused: java.lang.IllegalArgumentException: Failed to instantiate class hudson.node_monitors.DiskSpaceMonitor from {"freeSpaceThreshold":"1GiB"}
	at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:771)
	at org.kohsuke.stapler.RequestImpl.bindJSON(RequestImpl.java:551)
	at org.kohsuke.stapler.RequestImpl.bindJSON(RequestImpl.java:546)
	at hudson.model.Descriptor.bindJSON(Descriptor.java:623)
	at hudson.model.Descriptor.newInstance(Descriptor.java:593)
Caused: java.lang.LinkageError: Failed to instantiate class hudson.node_monitors.DiskSpaceMonitor from {"freeSpaceThreshold":"1GiB"}
	at hudson.model.Descriptor.newInstance(Descriptor.java:596)
	at hudson.util.DescribableList.rebuild(DescribableList.java:183)
	at hudson.model.ComputerSet.doConfigSubmit(ComputerSet.java:355)
	at …