Get rid of unmaintained django-parler (fixes DEV-159)

[aptiko]

Checklist:

• All tests are passing
• I have added any necessary documentation and/or release notes
• I have followed the commit message guidelines and the "before submitting a pull request" guidelines
• If I introduced (or abolished) any third-party library, I will write a short paragraph in this PR according to the guidelines
• I have removed all obsoleted code

[codecov]

Codecov Report

❌ Patch coverage is 92.59259% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 97.58%. Comparing base (889531a) to head (aa75b6d).
⚠️ Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
enhydris/models/timeseries_group.py	90.69%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #552      +/-   ##
==========================================
+ Coverage   97.48%   97.58%   +0.09%     
==========================================
  Files          55       55              
  Lines        3542     3560      +18     
==========================================
+ Hits         3453     3474      +21     
+ Misses         89       86       -3     

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[Copilot]

Pull request overview

This PR replaces the unmaintained django-parler library with a custom VariableTranslation model for handling multi-language variable descriptions in the Enhydris water data management system. The migration is done in three steps: creating a new translation table, copying data, then removing the old parler-managed table.

Changes:

• Replaced TranslatableModel/TranslatedFields from django-parler with a custom Variable model and VariableTranslation model, implementing a descr property with per-instance caching and language-aware resolution
• Added three data migrations (0121-0123) to safely migrate existing translation data from parler's table schema to the new custom table
• Updated all tests across the codebase to use the new Variable.objects.create() + variable.translations.create() pattern instead of baker.make(Variable, descr=...)

Reviewed changes

Copilot reviewed 28 out of 28 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
enhydris/models/timeseries_group.py	Core change: replaces parler-based Variable with plain Django model, adds VariableTranslation model, custom VariableManager, and descr property with caching
enhydris/models/__init__.py	Exports new VariableTranslation model
enhydris/admin/__init__.py	Replaces TranslatableAdmin with ModelAdmin + TabularInline for translations
enhydris/api/serializers.py	Replaces TranslatableModelSerializer with ModelSerializer + SerializerMethodField for translations
enhydris/api/views.py	Adds Prefetch for variable translations in the CSV endpoint
enhydris_project/settings/__init__.py	Removes parler from INSTALLED_APPS
enhydris_project/settings/ci.py	Removes PARLER_LANGUAGES setting
enhydris/migrations/0121_remove_parler_part1.py	Creates NewVariableTranslation table
enhydris/migrations/0122_remove_parler_part2.py	Copies data from old parler table to new table
enhydris/migrations/0123_remove_parler_part3.py	Deletes old table, renames new table
enhydris/tests/test_models/test_timeseries_group.py	Updates Variable tests for new translation model
enhydris/tests/test_models/test_timeseries.py	Updates query count assertions and cache clearing for new translation queries
enhydris/tests/test_models/test_gentity.py	Updates variable creation pattern
enhydris/tests/__init__.py	Updates test mixins for new translation pattern
enhydris/tests/admin/test_station.py	Updates variable creation pattern
enhydris/api/tests/test_views/*.py	Updates API tests for new variable creation and translation assertions
enhydris/api/tests/test_serializers.py	Updates serializer test for new variable creation
enhydris/autoprocess/tests/test_models/*.py	Updates autoprocess tests for new variable creation
enhydris/telemetry/tests/test_models.py	Updates telemetry tests for new variable creation
enhydris/synoptic/tests/data.py	Updates synoptic test data for new variable creation

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[aptiko]

@codex review

[chatgpt-codex-connector]

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Reviewed commit: 0809aea934

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[Copilot]

Pull request overview

Copilot reviewed 28 out of 28 changed files in this pull request and generated 1 comment.

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