feat: add ncbi taxonomy information to database

[emilylm]

📌 Summary

This PR adds NCBI taxonomy enrichment support to the API and updates the organism/taxonomy data model to separate BPA-supplied organism fields from NCBI-derived taxonomy fields.

It introduces the NCBI lookup service, stores fetched taxonomy details on taxonomy_info, updates the relevant models and schemas, and adds bulk-import support plus validation and tests around the new behavior.

We also re-set 0001-initial-schema.sql and clear previous db migrations

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🔄 Type of Change

• 🐛 Bug fix (non-breaking change that fixes an issue)
• ✨ New feature (non-breaking change that adds functionality)
• 💥 Breaking change (fix or feature that would cause existing functionality to change)
• 🧹 Refactor (code change that neither fixes a bug nor adds a feature)
• ⚙️ CI / build / tooling change

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🧩 Key Changes

• Added an Alembic migration and schema/model updates to move NCBI taxonomy detail fields onto taxonomy_info and rename organism source fields to bpa_*.
• Added ncbi_taxonomy_service to fetch and map taxonomy details from the NCBI Datasets API, including lineage enrichment and mito_ref. This code is largely across from https://github.com/emilylm/tutorial-fetch-ncbi-data/blob/main/src/parent_lineage_enrichment.py
• Updated taxonomy_info create and bulk-import flows to fetch and persist NCBI taxonomy details, with bulk import using batched lookups.
• Added stricter request validation so ncbi_* fields are not accepted from callers, including a typed bulk taxonomy-info import schema.
• Updated organism and assembly-related code to align with the new field names and taxonomy-info relationship usage.
• Added service and endpoint tests covering NCBI enrichment, bulk import behavior, and request validation.
• Removed previous database migrations and created an immutable 0001-initial-schema.sql

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✅ Checklist

• Tests are passing locally / in CI
• New tests have been added for new or changed functionality
• Self-review completed
• Documentation updated (if needed)
• No sensitive data or secrets included

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🔍 Review Notes

• This PR includes a schema/API shape change for organism fields: BPA/source values now use bpa_* names.
• For both the create and bulk-create endpoints, if a row already exists in taxonomy_info with the provided taxon_id, we update the existing taxonomy_info object.

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📎 Related Issues / Tickets

• Closes # AP-396
• Related to #