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[wxiaoguang]

Close #24104

This also introduces many tests to cover many complex error handling functions.

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After

The details could be shown to site admin users. It is safe.

[HesterG]

Tested and the issue is fixed, so LGTM

[codecov-commenter]

Codecov Report

Merging #24110 (14c8422) into main (f521e88) will decrease coverage by 0.04%.
The diff coverage is 41.65%.

@@            Coverage Diff             @@
##             main   #24110      +/-   ##
==========================================
- Coverage   47.14%   47.10%   -0.04%     
==========================================
  Files        1149     1161      +12     
  Lines      151446   153766    +2320     
==========================================
+ Hits        71397    72433    +1036     
- Misses      71611    72812    +1201     
- Partials     8438     8521      +83     

Impacted Files	Coverage Δ
cmd/dump.go	0.64% <0.00%> (-0.03%)	⬇️
cmd/embedded.go	0.00% <0.00%> (ø)
cmd/mailer.go	0.00% <0.00%> (ø)
cmd/manager.go	0.00% <0.00%> (ø)
cmd/manager_logging.go	0.00% <0.00%> (ø)
cmd/migrate_storage.go	5.76% <0.00%> (-0.12%)	⬇️
cmd/restore_repo.go	0.00% <0.00%> (ø)
cmd/web.go	0.00% <0.00%> (ø)
models/actions/run.go	1.63% <0.00%> (-0.10%)	⬇️
models/actions/runner.go	1.44% <ø> (ø)
... and 61 more

... and 153 files with indirect coverage changes

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