SCKAN-450 fix: Set population index on invalid statements

[afonsobspinto]

Closes https://metacell.atlassian.net/browse/SCKAN-450

I believe the problem was caused by the fact that statements that were originally ingested into invalid state never got a population_index.

To fix it, this PR:

• Creates a django command that synchronizes the population_index of all exported/invalid statements with the expected population_index according to the curie_id. See the command readme for more details. (fixes the current problems)
• Updates the transition to Invalid to set the population_index (prevents this from happening again)

When deployed run:
python manage.py reassign_population_indices --dry-run

And if you are happy with the changes that would happen run without the --dry-run flag.

Example of log file when running the command locally:

population_index_reassignment_2025-11-05_12-23-17.log

[Copilot]

Pull Request Overview

This PR addresses an issue where statements that were originally ingested into an invalid state never received a population_index. The fix ensures that all exported/invalid statements have consistent population indices based on their curie_id values.

Key Changes:

• Updates the invalid state transition to properly set the population_index by calling _perform_export_logic() instead of just setting the has_statement_been_exported flag
• Adds a Django management command to synchronize existing population indices with expected values based on curie_id patterns
• Includes comprehensive documentation for the new management command

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
applications/composer/backend/composer/models.py	Updates the invalid transition method to use _perform_export_logic() to ensure population_index is set
applications/composer/backend/composer/management/commands/reassign_population_indices.py	Adds a new Django management command that synchronizes population indices for exported statements based on their curie_id patterns
applications/composer/backend/composer/management/commands/README_reassign_population_indices.md	Provides detailed documentation for the new management command including usage examples and expected behavior

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[afonsobspinto]

Note:
With this new command I made it so that the population_index are synced with the curie_id when possible but this is a band-aid solution to the real problem addressed in #524 (comment).
To have a proper solution we need to understand from neurondm:

• how are the statements created in composer re-ingested in neurondm, will aacar 16 in composer be aacar 16 in neurondm.
• how to handle on composer side when neurondm curie_id name has an hyphen in the population index space like:
  neuron type femrep 40-3
  neuron type femrep 40-2