[FE] VSA - Switch to table layout for individual stages

What does this MR do?

This MR introduces the new stage table design, this replaces the existing stage table with the new stage table design for value stream analytics and updates related tests. This change only applies when the value_stream_analytics_path_navigation feature flag is enabled.

This MR:

• Adds the new stage table to the base.vue for value stream analytics
• Updates related feature specs based on the new stage table

Feature flag

value_stream_analytics_path_navigation: enables the path navigation UI - this feature flag is now default enabled

Screenshots (strongly suggested)

Does this MR meet the acceptance criteria?

Conformity

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  • I have not included a changelog entry because _____.
• Documentation (if required)
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• 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 #277380 (closed)