feat(cot): OpenTAK Server TCP integration + entity type filter

[d3mocide]

Summary

• Switch emitter from UDP to TCP when COT_TAKSERVER_HOST is set. OpenTAK Server (OTS) has no UDP CoT listener — it only accepts CoT via TCP on port 8088. The emitter now opens a persistent TCP connection with exponential-backoff reconnect, matching the receiver's pattern.
• Consolidate receiver config — COT_RECEIVE_HOST and COT_RECEIVE_PORT are removed. Both emitter and receiver connect to the same OTS endpoint (COT_TAKSERVER_HOST / COT_TAKSERVER_PORT). COT_RECEIVE_ENABLED remains as a simple boolean gate.
• Add COT_ENTITY_TYPES filter — comma-separated list of entity types to emit. Empty (default) emits everything. Filtered at the Redis message level before any TCP write.
• Echo loop guard — receiver now skips CoT events with UIDs prefixed VERTEX-, preventing OTS from echoing Vertex's own transmissions back as duplicate entities.

Config for OpenTAK Server

COT_ENABLED=true
COT_TAKSERVER_HOST=<ots-ip>
COT_TAKSERVER_PORT=8088        # OTS TCP CoT streaming port
COT_STALE_SECONDS=60
COT_RECEIVE_ENABLED=true

# Optional — leave blank to emit all types
COT_ENTITY_TYPES=aircraft,vessel,fire_incident

Entity types available for COT_ENTITY_TYPES

Type	Source
aircraft	ADS-B (Beast / OpenSky)
vessel	AIS
aprs	APRS packet radio
mesh_node	Meshtastic / MeshCore
train	Amtrak + GTFS-RT rail
fire_incident	NIFC / fire.gov
stream_gauge	USGS stream gauges
rf_sensor	RTL-433
tak_client	TAK field operators from OTS

Test plan

• COT_TAKSERVER_HOST set: emitter log shows TCP connected to TAK server not UDP multicast
• Entities appear in OTS web UI / connected ATAK clients
• COT_ENTITY_TYPES=aircraft,vessel — only aircraft and vessel CoT reach OTS
• COT_ENTITY_TYPES= (blank) — all entity types flow through
• ATAK field operator positions appear on Vertex map as tak_client entities
• No VERTEX- echo entities appear on Vertex map from OTS loopback
• COT_TAKSERVER_HOST blank: emitter falls back to UDP multicast, ATAK devices on LAN receive CoT

🤖 Generated with Claude Code

https://claude.ai/code/session_01PswxT6xcRYioF1ZfgszgRi

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Generated by Claude Code