Local export history

[Ezequiel-Valencia]

Summary

This PR implements a complete Export History feature that persists and exposes a paginated record of each user's simulation export
operations. When a user exports simulation data, the export details are saved to a new database table. Users can then query their export
history through a new REST endpoint.

What was changed

• Database layer — New vc_simulation_export_history table (PostgreSQL) stores export metadata: job ID,
  simulation/biomodel/mathmodel/math key references, export format, timestamp, output URI, exported variables, time range, and event
  status. Implements insert, paginated query (100 records per page, ordered by date DESC), and delete-by-URI operations.

• ExportSpecs enrichment — Added bioModelKey, mathModelKey, and mathDescriptionKey fields so that export requests carry the
  model references needed to populate the history table.

• REST endpoint — New GET /api/v1/export/history?pageNumber=N endpoint (requires user role) returns a paginated list of
  ExportHistory records for the authenticated user.

• OpenAPI spec & generated clients — Updated openapi.yaml with the new endpoint and ExportHistory, ExportFormat, and
  DifferentParameterValues schemas. Regenerated Java (vcell-restclient), Python (python-restclient), and TypeScript/Angular
  (webapp-ng) clients.

• Tests — DB-level tests verify insert, delete, and multi-record retrieval with model-name joins. Client integration tests cover
  end-to-end export → history flow, ordering (most-recent-first), and pagination boundaries.

Test plan

• ExportHistoryDBTest — unit tests for DB CRUD operations pass against a real test database
• ExportHistoryClientTest — integration tests verify the REST endpoint returns correct history, ordering, and page boundaries
• ExportRequestTest / ExportServerTest — existing export tests still pass with updated ExportSpecs constructor
• Manual smoke test: perform an export via the UI, then call GET /api/v1/export/history and confirm the record appears with correct
  metadata

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Notes

• The DELETE endpoint (DELETE /api/v1/export/history) exists in ExportResource.java but is currently marked hidden in the OpenAPI spec —
  it is not included in the PR description.
• Page size is fixed at 100; pageNumber is 0-indexed and validated to be in [0, 9999].