[DOP-23867] Change API schema for lineage endpoints

[dolfinus]

Change Summary

Using flat lists for all relation types and node types is not very efficient to use on client/UI side.

Instead, split relations to different lists, one for each relation type, and split nodes to differents dict[id, Node], one for each node type. This is more efficient to use, because we can replace O(n) filters with O(n) with much smaller n, or even with O(1).

As JSON format requires all object keys to be strings, change id types for dataset, job and location from int to str. This is applied only to API responses, but not to query params, as DB models still have numeric primary keys.

This also get rid of Union response types, so we can update Pydantic to 2.10 and not suffer from slowdown during serialization.

Related issue number

Checklist

• Commit message and PR title is comprehensive
• Keep the change as small as possible
• Unit and integration tests for the changes exist
• Tests pass on CI and coverage does not decrease
• Documentation reflects the changes where applicable
• docs/changelog/next_release/<pull request or issue id>.<change type>.rst file added describing change
  (see CONTRIBUTING.rst for details.)
• My PR is ready to review.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.17%. Comparing base (d9ac4dd) to head (3dbda93).
Report is 132 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #164      +/-   ##
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+ Coverage    93.16%   93.17%   +0.01%     
===========================================
  Files          185      185              
  Lines         4228     4236       +8     
  Branches       281      279       -2     
===========================================
+ Hits          3939     3947       +8     
  Misses         227      227              
  Partials        62       62              

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