Map Perch model outputs

[nnethery]

We map Perch outputs (scientific names) to common names, and optionally (by default) to the BirdNet subset.

Filtering Logic

1. Hybrid Matching: Accepts detections matching BirdNET via Scientific Name OR Common Name.
   • Fixes taxonomy mismatches (e.g., Dartford Warbler: Sylvia vs Curruca).
2. Excluded Categories: Silently drops all non-avian classes:
   • Amphibians (Frogs/Toads), Insects, Mammals, Environmental (Rain/Wind), Instruments, and Mechanical sounds.
3. Perch-Only Birds: ~843 legitimate bird species (endemics/rare) are dropped because they are absent from BirdNET.

Disable filter (PERCH_BIRDNET_FILTER=0) to retain the results from categories 2 and 3.

Coverage Stats

Category	Count	Notes
Accepted	6,829	Perch birds matching BirdNET list.
Missing	126	BirdNET species Perch cannot detect (1.8%).
Dropped	~843	Valid Perch birds ignored to maintain BirdNET parity.