remove panic & wrapping informational error

[emplam27]

What this PR does / why we need it:

ref. https://github.com/uber-go/guide/blob/master/style.md#dont-panic

Remove panic() in server production

• Change function from using panic to return error and caller to decide how to handle it.
• Wrapping error more informationally

Remove panic method & Wrapping errors in CRDT logics

• Currently, if error occurred in CRDT logic, server was shutdown because of panic() method
• Removed panic() methods & Change all errors able to logging

Which issue(s) this PR fixes:

Fixes #497

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

Additional documentation:

Checklist:

• Added relevant tests or not required
• Didn't break anything

[codecov]

Codecov Report

Merging #501 (49e70c8) into main (969e509) will decrease coverage by 1.63%.
The diff coverage is 29.37%.

@@            Coverage Diff             @@
##             main     #501      +/-   ##
==========================================
- Coverage   50.61%   48.98%   -1.63%     
==========================================
  Files          64       64              
  Lines        5751     5985     +234     
==========================================
+ Hits         2911     2932      +21     
- Misses       2471     2615     +144     
- Partials      369      438      +69     

Impacted Files	Coverage Δ
api/converter/to_bytes.go	83.33% <0.00%> (ø)
api/converter/to_pb.go	63.87% <0.00%> (ø)
api/types/client.go	0.00% <0.00%> (ø)
client/client.go	15.38% <ø> (ø)
internal/validation/validation.go	45.52% <0.00%> (+0.72%)	⬆️
pkg/document/change/change.go	0.00% <0.00%> (ø)
pkg/document/crdt/object.go	20.51% <12.50%> (-3.02%)	⬇️
pkg/document/internal_document.go	21.87% <14.28%> (-0.16%)	⬇️
api/converter/from_pb.go	51.93% <14.45%> (-1.72%)	⬇️
pkg/document/crdt/array.go	24.63% <16.21%> (-11.73%)	⬇️
... and 12 more

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[hackerwins]

Thanks for your contribution.

I think the interface has changed only for the function below:

• validation.RegisterValidation
• validation.RegisterTranslation
• config.configPath
• time.ParseDuration

Next, it would be nice to remove the panic that can occur in CRDT data structure.

[hackerwins]

Thanks for the second work. I leave a few comments.

We need to check whether an actual error can occur

While removing panic, some interfaces have been changed to return an error. The changes may reduce the usability of interfaces, It is necessary to check whether an actual error can occur.

For example, there is a situation like below:

An error chain Text.String > RGATreeSplitNode.String > TextValue.String need not return an actual error.

func (t *TextValue) String() (string, error) {
	return t.value, nil
}