[#28187][prism] Add a debugz page to standalone web ui.

[lostluck]

Add a page to the stand alone command that produces the various Go runtime metrics of the binary.

In particular, this includes the formatted goroutine dump, which can be useful in investigating stuck or unusually behaving jobs, when expanding prism's abilities.

Available at /debugz or from the link at the bottom of the index page.

Related to #28187.

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[codecov]

Codecov Report

Merging #28183 (6a6b09a) into master (e26735d) will increase coverage by 0.01%.
Report is 1 commits behind head on master.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #28183      +/-   ##
==========================================
+ Coverage   72.29%   72.31%   +0.01%     
==========================================
  Files         678      678              
  Lines       99848    99848              
==========================================
+ Hits        72189    72203      +14     
+ Misses      26084    26068      -16     
- Partials     1575     1577       +2     

Flag	Coverage Δ
go	53.66% <ø> (+0.03%)	⬆️

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see 1 file with indirect coverage changes

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[jrmccluskey]

Do you have an example of what the page looks like?

[lostluck]

Do you have an example of what the page looks like?

Screen shots added. Basically same formatting as the main and job details pages. Uses pre-formatted cells so the goroutine dump appears correctly.

[jrmccluskey]

LGTM