feat: Add position ambiguity support from APRS parser

- Added position_ambiguity field (integer, 0-4) to packets table
- Created migration to add the new database column
- Updated packet schema and processing to extract position ambiguity
- Position ambiguity levels indicate precision of reported coordinates:
  - 0: No ambiguity (exact position)
  - 1: ~0.1 mile ambiguity
  - 2: ~1 mile ambiguity
  - 3: ~10 mile ambiguity
  - 4: ~60 mile ambiguity
- Automatically captures ambiguity level when parsing APRS packets
- All tests pass with no failures

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

CHANGELOG.md

@@ -22,6 +22,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   - Automatically drains connections when node is overloaded (>70% CPU or 2x average connections)
   - Gracefully reconnects clients to less loaded nodes
   - Improves overall cluster stability and performance
+- Position ambiguity support from APRS parser
+  - Added `position_ambiguity` field to packets table (integer, 0-4)
+  - Automatically captures position ambiguity level when parsing APRS packets
+  - Supports ambiguity levels 0-4 as defined in APRS specification
 
 ### Changed
 - Query performance improved by 50-90% for common operations

lib/aprsme/packet.ex

@@ -52,6 +52,9 @@ defmodule Aprsme.Packet do
     field(:speed, :float)
     field(:altitude, :float)
 
+    # Position ambiguity level (0-4)
+    field(:position_ambiguity, :integer)
+
     # PHG (Power-Height-Gain) fields
     field(:phg_power, :integer)
     field(:phg_height, :integer)
@@ -115,6 +118,7 @@ defmodule Aprsme.Packet do
       :course,
       :speed,
       :altitude,
+      :position_ambiguity,
       :phg_power,
       :phg_height,
       :phg_gain,
@@ -346,6 +350,7 @@ defmodule Aprsme.Packet do
       :aprs_messaging,
       data_extended[:aprs_messaging?] || data_extended["aprs_messaging?"]
     )
+    |> maybe_put(:position_ambiguity, data_extended[:position_ambiguity] || data_extended["position_ambiguity"])
   end
 
   defp put_weather_fields(map, data_extended) do

priv/repo/migrations/20250801211702_add_position_ambiguity_to_packets.exs

@@ -0,0 +1,9 @@
+defmodule Aprsme.Repo.Migrations.AddPositionAmbiguityToPackets do
+  use Ecto.Migration
+
+  def change do
+    alter table(:packets) do
+      add :position_ambiguity, :integer
+    end
+  end
+end

vendor/aprs

@@ -1 +1 @@
-Subproject commit 49b5225fe8b3212bab2833cfbf1032a030010022
+Subproject commit 46ece8d819b6ceb67b55dfe689cab68c665c978b