implement schema validation for vendoring and schemas

[samtholiya]

Why Draft

• Need schema for 3 atmos examples mentioned here: https://linear.app/cloudposse/issue/DEV-2987/generalize-atmos-schema-validation#comment-14f6fb61
  1. config

what

• Added a new validator command to the CLI.
• This command verifies the YAML structure of the atmos CLI.
• If a schema key is present in the YAML, it validates the structure against the schema.

why

• Ensures that configuration files follow the correct YAML structure.
• Prevents misconfigurations and errors caused by invalid or malformed YAML.
• Adds an extra layer of validation by enforcing schema compliance when applicable.
• Improves reliability and usability of the CLI by catching issues early.

references

• DEV-3030
• Support Multiple Schema Validations #1066

[codecov]

Codecov Report

Attention: Patch coverage is 45.13274% with 248 lines in your changes missing coverage. Please review.

Project coverage is 26.46%. Comparing base (9e0823c) to head (eca159c).

Files with missing lines	Patch %	Lines
pkg/filematch/mock_interface.go	0.00%	76 Missing ⚠️
internal/exec/validate_schema.go	44.77%	27 Missing and 10 partials ⚠️
pkg/datafetcher/mock_fetch_schema.go	0.00%	30 Missing ⚠️
pkg/validator/schema_validator.go	52.83%	19 Missing and 6 partials ⚠️
cmd/validate_schema.go	17.39%	19 Missing ⚠️
pkg/filematch/filematch.go	81.48%	10 Missing and 5 partials ⚠️
pkg/validator/mock_schema_validator.go	0.00%	15 Missing ⚠️
pkg/downloader/mock_file_downloader_interface.go	0.00%	9 Missing ⚠️
pkg/datafetcher/fetch_schema.go	75.00%	5 Missing and 1 partial ⚠️
pkg/utils/markdown_utils.go	0.00%	4 Missing ⚠️
... and 5 more

Additional details and impacted files

@@                                           Coverage Diff                                           @@
##           feature/dev-3056-refactor-gogetter-utility-for-better-testability-2    #1147      +/-   ##
=======================================================================================================
+ Coverage                                                                26.06%   26.46%   +0.39%     
=======================================================================================================
  Files                                                                      183      197      +14     
  Lines                                                                    20687    21135     +448     
=======================================================================================================
+ Hits                                                                      5392     5593     +201     
- Misses                                                                   14449    14672     +223     
- Partials                                                                   846      870      +24     

Flag	Coverage Δ
unittests	26.46% <45.13%> (+0.39%)	⬆️

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[mergify]

💥 This pull request now has conflicts. Could you fix it @samtholiya? 🙏

[mergify]

Important

Cloud Posse Engineering Team Review Required

This pull request modifies files that require Cloud Posse's review. Please be patient, and a core maintainer will review your changes.

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