GOATS-961 GOATS-983: Add clone target and observation serializers.

[davner]

• Update GPP API views to utilize the new serializers for cloning functionality.
• Add unit tests for the new serializers.

Checklist

• Added a release note in doc/changes using the PR number.

[Copilot]

Pull Request Overview

This PR introduces new serializers for cloning GPP targets and observations, enabling target and observation duplication through the ToO form with proper validation of input data.

• Adds CloneTargetSerializer and CloneObservationSerializer to handle and validate clone operation inputs
• Updates GPPTooViewSet to use the new serializers via _format_clone_observation_input and _format_clone_target_input methods
• Includes comprehensive unit tests validating both successful and error scenarios for the new serializers

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/goats_tom/serializers/gpp/clone_target.py	New serializer for validating and formatting target clone inputs including radial velocity, parallax, and proper motion
src/goats_tom/serializers/gpp/clone_observation.py	New serializer for validating and formatting observation clone inputs with constraint sets and position angle validation
src/goats_tom/serializers/gpp/init.py	Exports the new clone serializers for module-level access
src/goats_tom/api_views/gpp/toos.py	Adds methods to format clone inputs using the new serializers and updates exception handling to use proper ValidationError
tests/goats_tom/serializers/gpp/test_clone_target.py	Unit tests for CloneTargetSerializer covering valid inputs and validation errors
tests/goats_tom/serializers/gpp/test_clone_observation.py	Unit tests for CloneObservationSerializer including angle constraint validation
tests/goats_tom/api_views/gpp/test_toos.py	Test coverage for the new formatting methods and updated existing tests to use correct exception types

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[codecov]

Codecov Report

❌ Patch coverage is 98.05195% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 78.70%. Comparing base (9a9229a) to head (6fee0c8).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/goats_tom/serializers/gpp/clone_observation.py	93.93%	2 Missing ⚠️
src/goats_tom/serializers/gpp/clone_target.py	94.73%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #465      +/-   ##
==========================================
+ Coverage   78.36%   78.70%   +0.33%     
==========================================
  Files         256      260       +4     
  Lines        8164     8307     +143     
  Branches      487      489       +2     
==========================================
+ Hits         6398     6538     +140     
- Misses       1677     1680       +3     
  Partials       89       89              

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