Serialize AdvisoryPackage.package_name in v3 JSON

[atomicturtle]

Summary

• packages[].package_name was always null because Tortoise pydantic only emits computed methods, and the cleaned name lived on a property over _package_name.
• Keep attribute access for workers/updateinfo, but expose the cleaned name as a computed field so GET /api/v3/advisories/{id} serializes package_name.

Test plan

• python -m unittest apollo.tests.test_advisory_package
• After deploy, curl -s https://apollo.build.resf.org/api/v3/advisories/RLSA-2024:1444 | jq '.packages[0].package_name' is a non-null RPM name (e.g. nodejs), not null.

Closes #94

[rockythorn]

Review: Request changes (one fix needed, then approve)

Tested locally against a prod DB snapshot. The serialization fix works correctly.

Verified

• GET /api/v3/advisories/RLSA-2024:1444 now returns package_name: "nodejs" instead of null
• module. prefix is correctly stripped (no module.-prefixed names in output)
• No null package_name values on packages that have names in the DB
• The descriptor pattern is well-documented and correctly satisfies Tortoise pydantic's requirement for a callable with return annotation
• _clean_package_name converted to @staticmethod — good, no need for self
• replace('module.', '', 1) — fixes a real edge case where double module.module. would be over-stripped

Fix needed

test_advisory_package.py is not registered in BUILD.bazel or .github/workflows/test.yaml. The test file exists but will never run in CI. Per project guidelines:

1. Add a py_test entry to apollo/tests/BUILD.bazel:

py_test(
    name = "test_advisory_package",
    srcs = ["test_advisory_package.py"],
    deps = [
        "//apollo/db:db_lib",
    ],
)

2. Add to .github/workflows/test.yaml in the "Unit Tests" section.

Design note (non-blocking)

The _PackageName descriptor is the cleverest code in the model layer. The docstring explains the why well. Future maintainers should know this exists if they ever touch Tortoise pydantic computed fields.

[atomicturtle]

Registered test_advisory_package in apollo/tests/BUILD.bazel and .github/workflows/test.yaml so CI actually runs it. Also merged current main.

Still just the v3 JSON serialization fix for review — not a production catalog change.