fix(neo_feed): missing-distance false ALERT + UTC feed window

[THOClabs]

Summary

Fixes two correctness issues in the just-merged NEO feed client (#108), both flagged by Cursor Bugbot and independently verified against the source.

• High — false ALERT on missing distance. _parse_neo_object defaulted distance_au/distance_ld to 0 when miss_distance.astronomical was absent. Since threat_level returns ALERT when distance_ld < 1.0, a NEO with unknown distance was mis-classified as a close pass. Now: prefer astronomical, fall back to deriving AU from kilometers, and skip the object if neither is present.
• Medium — local vs UTC feed window. The default start_date used date.today() (local) while the CAD client and all NEO timing are UTC, shifting the query window a day near timezone boundaries. Now uses datetime.now(timezone.utc).date().

Testing

• Two regression tests added: missing-distance is skipped (not a phantom ALERT); km-only distance correctly derives AU.
• pytest tests/unit/test_neo_feed_client.py tests/unit/test_neo_client.py → 65 passed

🤖 Generated with Claude Code

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Generated by Claude Code

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Note

Medium Risk
Changes threat classification inputs for NEO feed data; incorrect parsing could still miss real alerts, but the fix removes a known false-positive path in meteor tracking.

Overview
Fixes two correctness bugs in NEO feed parsing that could mis-rank threats or query the wrong date window.

Miss distance handling no longer treats absent miss_distance as zero AU/LD. The parser prefers astronomical, derives AU from kilometers when needed, and drops objects with no distance so they cannot hit threat_level ALERT via distance_ld < 1.0.

Default feed window now anchors start_date on UTC (datetime.now(timezone.utc).date()) instead of local date.today(), aligning with the CAD client and NEO timing.

Unit tests cover skipped missing-distance and km-only distance derivation.

^{Reviewed by Cursor Bugbot for commit 042a089. Bugbot is set up for automated code reviews on this repo. Configure here.}