Feat: vela cuex eval

[Somefive]

Description of your changes

Support running cuex eval command in vela CLI.

$ vela help cuex eval
Eval cue file with CueX engine.

 Evaluate your cue file with the CueX engine. When your cue file does not use KubeVela's extension, it will work
similarly to the native CUE CLI. When using KubeVela's extensions, this command will execute the extension functions and
resolve values, in addition to the native CUE compile process.

Usage:
  vela cuex eval [flags]

Examples:
  # Evaluate a cue file
  vela cuex eval -f my.cue
  
  # Evaluate a cue file into json format
  vela cuex eval -f my.cue -o json
  
  # Evaluate a cue file and output the target path
  vela cuex eval -f my.cue -p key.path

Flags:
  -f, --file string     file for eval
  -o, --format string   format of the output (default "cue")
  -p, --path string     path for eval

Global Flags:
  -y, --yes   Assume yes for all user prompts

Solves #5862

I have:

• Read and followed KubeVela's contribution process.
• Related Docs updated properly. In a new feature or configuration option, an update to the documentation is necessary.
• Run make reviewable to ensure this PR is ready for review.
• Added backport release-x.y labels to auto-backport this PR if necessary.

How has this code been tested

Special notes for your reviewer

[codecov]

Codecov Report

Patch coverage has no change and project coverage change: -0.01 ⚠️

Comparison is base (9042ed0) 61.35% compared to head (554d471) 61.34%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5562      +/-   ##
==========================================
- Coverage   61.35%   61.34%   -0.01%     
==========================================
  Files         224      224              
  Lines       31121    31121              
==========================================
- Hits        19093    19091       -2     
- Misses      10233    10235       +2     
  Partials     1795     1795              

Flag	Coverage Δ
core-unittests	55.81% <ø> (+0.02%)	⬆️
e2e-multicluster-test	24.87% <ø> (-0.03%)	⬇️
e2etests	26.95% <ø> (-0.05%)	⬇️

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see 7 files with indirect coverage changes

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