Clean up session's Segments

[linear]

Now that the new session experience is in for a few weeks, we can go back and clean up some of the unused code. This is the segments table and related graphql methods.

[linear]

HIG-4678 Clean up session's Segments

[greptile-apps]

To clean up the session's Segments, follow these steps:

1. Remove Segments Table:

   • Navigate to backend/clickhouse.
   • Identify and remove the segments table definition and any related code.

2. Remove Related GraphQL Methods:

   • Navigate to backend/private-graph/graph/generated/generated.go.
   • Identify and remove the GraphQL methods related to segments.

Ensure all references to the segments table and GraphQL methods are removed from the codebase.

References