GOATS-985 GOATS-987: Build payload for creating ToO.

[davner]

• Added target ID to form data in GPPModel's createTooObservation method.
• Updated test suite for GPPTooViewSet to remove deprecated tests and add new tests for observing mode properties.
• Refactored GMOS North and South Long Slit serializers to include nested structure for inputs.
• Simplified tests for CloneTargetSerializer and CloneObservationSerializer, focusing on essential fields.
• Introduced new tests for ObservingModeSerializer and SiderealSerializer to ensure validation and serialization logic.
• Corrected code and unit tests to reflect changes in field names from 'unit' to 'units' in brightness tests.
• Removed obsolete test files for CloneObservation and CloneTarget.

Checklist

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

[Copilot]

Pull Request Overview

This PR implements payload building functionality for creating Target of Opportunity (ToO) observations in GPP. The changes refactor serializers to use nested data structures, introduce new serializers for sidereal targets and observing modes, and update tests to reflect changes in field names and API structure. Key functionality includes appending target IDs to form data and properly structuring instrument-specific configurations.

• Introduced SiderealSerializer and ObservingModeSerializer for handling target and observing mode properties
• Refactored GMOS serializers to wrap validated data in instrument-specific keys (gmos_north_long_slit, gmos_south_long_slit)
• Updated field name from 'unit' to 'units' throughout brightness-related code

Reviewed Changes

Copilot reviewed 21 out of 21 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/goats_tom/static/js/gpp/gpp.js	Adds target ID to form data in createTooObservation method
src/goats_tom/serializers/gpp/sidereal.py	New serializer for sidereal target properties with validation
src/goats_tom/serializers/gpp/observing_mode.py	New serializer for observing mode input with instrument registry integration
src/goats_tom/serializers/gpp/instruments/registry.py	Simplified registry by removing input model mapping functionality
src/goats_tom/serializers/gpp/instruments/gmos_*.py	Added nested structure wrapping for validated data
src/goats_tom/serializers/gpp/clone_target.py	Simplified to only handle target ID validation
src/goats_tom/serializers/gpp/clone_observation.py	Added scienceRequirements field to validated data
src/goats_tom/serializers/gpp/brightnesses.py	Changed field name from 'unit' to 'units' and added debug print
src/goats_tom/api_views/gpp/toos.py	Refactored to use new serializers and added debug print statements
tests/goats_tom/serializers/gpp/test_*.py	Updated tests for new serializer behavior and field name changes
tests/goats_tom/api_views/gpp/test_toos.py	Removed deprecated tests and added new tests for observing mode

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[codecov]

Codecov Report

❌ Patch coverage is 82.96296% with 23 lines in your changes missing coverage. Please review.
✅ Project coverage is 78.63%. Comparing base (c919750) to head (a6522dc).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
src/goats_tom/api_views/gpp/toos.py	25.80%	23 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #467      +/-   ##
==========================================
- Coverage   78.91%   78.63%   -0.29%     
==========================================
  Files         264      269       +5     
  Lines        8390     8504     +114     
  Branches      490      493       +3     
==========================================
+ Hits         6621     6687      +66     
- Misses       1680     1727      +47     
- Partials       89       90       +1     

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