fix: repository audit remediation (CI, bugs, docs, packaging)

[isayev]

Summary

Addresses all findings from the 2026-04-08 repository audit across CI/CD, codebase bugs, tests, docs, and packaging.

CI/CD

• Remove broken cursor-code-review workflow (missing CURSOR_API_KEY secret)
• Add missing tests-hf CI job; add tests-hf to deploy-docs gate
• Add timeout-minutes: 20 to all jobs; fetch-depth: 0 to tests-core
• Remove silently-ignored branches filter from release event in on-release-main.yml
• Add concurrency group to GPU tests workflow to prevent runner queue buildup

Bug fixes

• Fix AIMNet2Calculator routing bug: relative two-segment paths (e.g. subdir/model.pt) matched the HF regex but had no fallthrough, leaving self.model unassigned
• Fix load_model_registry() ignoring its registry_file parameter (hardcoded path in open())
• Fix AIMNet2ASE species validation: implemented_species is stored in model._metadata, not as a direct attribute on the calculator
• Fix hf_hub.py: needs_coulomb, needs_dispersion, coulomb_mode now use _cfg() so GCS fallback is consulted when fields are missing from config.json
• Fix deprecated logging.warn → logging.warning

Codebase

• Add has_embedded_lr: NotRequired[bool] to ModelMetadata TypedDict
• Delete aimnet/base.py (dead code, superseded by aimnet/models/base.py)

Tests

• Add regression test for relative-path routing bug
• Add test_model_registry.py covering registry_file param
• Add AIMNet2ASE species validation tests
• Add session-scoped aimnet2_calc fixture to conftest.py

Docs

• Document ensemble_member, revision, token constructor params in calculator.md
• Add HF repo ID and local HF dir rows to the model parameter table

Packaging

• Add warp-lang<2 upper bound to prevent silent breakage on next major version
• Add Python 3.13 classifier

Test plan

• All CI jobs pass (quality, tests-core 3.11+3.12, tests-ase, tests-train, tests-pysis, tests-hf, check-docs)
• New tests-hf job runs and passes
• deploy-docs only triggers after all jobs green