Create package list vue component

What does this MR do?

This MR implements the vue component part of this refactor plan: !18860 (merged) MR: new vue component proposal and implementation

Caveats

• This component is not functional without vuex, it uses mock data ( that I removed ) to render and the tests to validate.
• The vuex 'connection points' are listed in a comment block
• Feature tests are not done since the feature is not 'operative' as it is.
• The components of this work are made keeping in mind that #31817 (closed) will soon need to be tackled ( hence way I organised the components as it is )

Note

The folder structure may seem wonky, by mixing list and details code, the reason is that an MR to move the details to his own folder is going to be kicked out once another MR touching those files is merged ( !18999 (merged) ) to avoid conflicts

All the work around !18860 (merged) is behind feature flag

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• [-] Label as security and @ mention @gitlab-com/gl-security/appsec
• [-] The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• [-] Security reports checked/validated by a reviewer from the AppSec team