feat: support --format for oras pull

[qweeah]

What this PR does / why we need it:
This PR

1. Adds support for --format [json|<go_template>] for pull command according to doc(spec): formatted ORAS CLI output #1199
2. Refactor status/metadata output

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Related to #638

Please check the following list:

• Does the affected code have corresponding tests, e.g. unit test, E2E test?
• Does this change require a documentation update?
• Does this introduce breaking changes that would require an announcement or bumping the major version?
• Do all new files have an appropriate license header?

[codecov]

Codecov Report

Attention: Patch coverage is 84.61538% with 28 lines in your changes are missing coverage. Please review.

Project coverage is 83.96%. Comparing base (c7ecf5c) to head (1e11eb4).

Files	Patch %	Lines
cmd/oras/root/pull.go	65.51%	4 Missing and 6 partials ⚠️
cmd/oras/internal/display/metadata/model/pull.go	75.75%	5 Missing and 3 partials ⚠️
cmd/oras/internal/display/status/tty.go	77.27%	5 Missing ⚠️
cmd/oras/internal/display/handler.go	82.35%	1 Missing and 2 partials ⚠️
cmd/oras/internal/display/utils/utils.go	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1293      +/-   ##
==========================================
+ Coverage   83.78%   83.96%   +0.17%     
==========================================
  Files          84       90       +6     
  Lines        3343     3448     +105     
==========================================
+ Hits         2801     2895      +94     
- Misses        322      331       +9     
- Partials      220      222       +2     

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[shizhMSFT]

LGTM