FE: Allow users to edit the status of a Jira issue on details page [RUN ALL RSPEC] [RUN AS-IF-FOSS]

What does this MR do?

Changes are behind feature flag jira_issue_details_edit_status while waiting for the backend.

• Add SidebarEditableItem component to allow editing of the status field on Jira issue details page. This follows the approach of other sidebar elements (issue assignees, iterations...)
• Add basic fetch / update approach that mimics actual backend endpoints.

Screenshots (strongly suggested)

Without feature flag (current)	With feature flag

Dropdown loading	Dropdown with items	Dropdown empty	Updating

Does this MR meet the acceptance criteria?

Conformity

• 📋 Does this MR need a changelog?
  • I have included a changelog entry.
  • I have not included a changelog entry because this is behind a feature flag.
• 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
• Informed Infrastructure department of a default or new setting change, if applicable per definition of done

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

Related to #328786 (closed)