Add 902-5760 MHz bands, centralize band options

New BandConfig entries for 902, 1296, 2304, 3456, 5760 MHz:
- All beneficial humidity effect (like 10 GHz)
- Near-zero gaseous absorption and rain attenuation
- Ranges: 902 MHz typical 400 km, 5760 MHz typical 220 km
- Same seasonal curves as 10 GHz (ducting-driven)

BandConfig.band_options/0 generates dropdown options from configs.
All pages (path, rover, submit) use centralized band_options instead
of hardcoded lists. Map page already used BandConfig.all_bands().
10 GHz remains the default on all pages.

lib/microwaveprop/propagation/band_config.ex

@@ -46,6 +46,146 @@ defmodule Microwaveprop.Propagation.BandConfig do
   @refractivity_default {42, 42}
 
   @band_configs %{
+    902 => %{
+      freq_mhz: 902,
+      label: "902 MHz",
+      o2_db_km: 0.006,
+      h2o_coeff: 0.0,
+      humidity_effect: :beneficial,
+      humidity_penalty: 0.0,
+      rain_k: 0.000,
+      rain_alpha: 1.0,
+      seasonal_base: %{
+        1 => 38,
+        2 => 40,
+        3 => 22,
+        4 => 55,
+        5 => 68,
+        6 => 90,
+        7 => 95,
+        8 => 75,
+        9 => 78,
+        10 => 88,
+        11 => 78,
+        12 => 25
+      },
+      seasonal_adj: %{},
+      typical_range_km: 400,
+      extended_range_km: 800,
+      exceptional_range_km: 1500
+    },
+    1_296 => %{
+      freq_mhz: 1_296,
+      label: "1296 MHz",
+      o2_db_km: 0.006,
+      h2o_coeff: 0.0,
+      humidity_effect: :beneficial,
+      humidity_penalty: 0.0,
+      rain_k: 0.000,
+      rain_alpha: 1.0,
+      seasonal_base: %{
+        1 => 38,
+        2 => 40,
+        3 => 22,
+        4 => 55,
+        5 => 68,
+        6 => 90,
+        7 => 95,
+        8 => 75,
+        9 => 78,
+        10 => 88,
+        11 => 78,
+        12 => 25
+      },
+      seasonal_adj: %{},
+      typical_range_km: 350,
+      extended_range_km: 700,
+      exceptional_range_km: 1200
+    },
+    2_304 => %{
+      freq_mhz: 2_304,
+      label: "2304 MHz",
+      o2_db_km: 0.006,
+      h2o_coeff: 0.0,
+      humidity_effect: :beneficial,
+      humidity_penalty: 0.0,
+      rain_k: 0.001,
+      rain_alpha: 1.15,
+      seasonal_base: %{
+        1 => 38,
+        2 => 40,
+        3 => 22,
+        4 => 55,
+        5 => 68,
+        6 => 90,
+        7 => 95,
+        8 => 75,
+        9 => 78,
+        10 => 88,
+        11 => 78,
+        12 => 25
+      },
+      seasonal_adj: %{},
+      typical_range_km: 300,
+      extended_range_km: 600,
+      exceptional_range_km: 1000
+    },
+    3_456 => %{
+      freq_mhz: 3_456,
+      label: "3456 MHz",
+      o2_db_km: 0.006,
+      h2o_coeff: 0.0,
+      humidity_effect: :beneficial,
+      humidity_penalty: 0.0,
+      rain_k: 0.002,
+      rain_alpha: 1.20,
+      seasonal_base: %{
+        1 => 38,
+        2 => 40,
+        3 => 22,
+        4 => 55,
+        5 => 68,
+        6 => 90,
+        7 => 95,
+        8 => 75,
+        9 => 78,
+        10 => 88,
+        11 => 78,
+        12 => 25
+      },
+      seasonal_adj: %{},
+      typical_range_km: 250,
+      extended_range_km: 550,
+      exceptional_range_km: 900
+    },
+    5_760 => %{
+      freq_mhz: 5_760,
+      label: "5760 MHz",
+      o2_db_km: 0.007,
+      h2o_coeff: 0.0,
+      humidity_effect: :beneficial,
+      humidity_penalty: 0.0,
+      rain_k: 0.005,
+      rain_alpha: 1.25,
+      seasonal_base: %{
+        1 => 38,
+        2 => 40,
+        3 => 22,
+        4 => 55,
+        5 => 68,
+        6 => 90,
+        7 => 95,
+        8 => 75,
+        9 => 78,
+        10 => 88,
+        11 => 78,
+        12 => 25
+      },
+      seasonal_adj: %{},
+      typical_range_km: 220,
+      extended_range_km: 500,
+      exceptional_range_km: 1000
+    },
     10_000 => %{
       freq_mhz: 10_000,
       label: "10 GHz",
@@ -292,6 +432,12 @@ defmodule Microwaveprop.Propagation.BandConfig do
     |> Enum.sort()
   end
 
+  @doc "Returns band options as {label, value_string} tuples for form dropdowns."
+  @spec band_options() :: [{String.t(), String.t()}]
+  def band_options do
+    Enum.map(all_bands(), fn band -> {band.label, to_string(band.freq_mhz)} end)
+  end
+
   @doc "Returns the scoring weights map. All 10 values sum to 1.0."
   @spec weights() :: map()
   def weights, do: @weights

lib/microwaveprop_web/live/path_live.ex

@@ -11,16 +11,7 @@ defmodule MicrowavepropWeb.PathLive do
   alias Microwaveprop.Terrain.TerrainAnalysis
   alias Microwaveprop.Weather
 
-  @band_options [
-    {"10 GHz", "10000"},
-    {"24 GHz", "24000"},
-    {"47 GHz", "47000"},
-    {"68 GHz", "68000"},
-    {"76 GHz", "75000"},
-    {"122 GHz", "122000"},
-    {"134 GHz", "134000"},
-    {"241 GHz", "241000"}
-  ]
+  @band_options BandConfig.band_options()
 
   @url_params ~w(source destination band src_height_ft dst_height_ft tx_power_dbm src_gain_dbi dst_gain_dbi)
   @defaults %{

lib/microwaveprop_web/live/rover_live.ex

@@ -6,18 +6,12 @@ defmodule MicrowavepropWeb.RoverLive do
   """
   use MicrowavepropWeb, :live_view
 
+  alias Microwaveprop.Propagation.BandConfig
   alias Microwaveprop.Radio.CallsignClient
   alias Microwaveprop.Radio.Maidenhead
   alias Microwaveprop.Rover.Coverage
 
-  @band_options [
-    {"10 GHz", "10000"},
-    {"24 GHz", "24000"},
-    {"47 GHz", "47000"},
-    {"76 GHz", "75000"},
-    {"122 GHz", "122000"},
-    {"241 GHz", "241000"}
-  ]
+  @band_options BandConfig.band_options()
 
   @impl true
   def mount(_params, _session, socket) do

lib/microwaveprop_web/live/submit_live.ex

@@ -3,25 +3,13 @@ defmodule MicrowavepropWeb.SubmitLive do
   use MicrowavepropWeb, :live_view
   use LiveStash
 
+  alias Microwaveprop.Propagation.BandConfig
   alias Microwaveprop.Radio
   alias Microwaveprop.Radio.Contact
   alias Microwaveprop.Radio.CsvImport
   alias Microwaveprop.Workers.ContactWeatherEnqueueWorker
 
-  @band_options [
-    {"1296 MHz", "1296"},
-    {"2304 MHz", "2304"},
-    {"3456 MHz", "3456"},
-    {"5760 MHz", "5760"},
-    {"10 GHz", "10000"},
-    {"24 GHz", "24000"},
-    {"47 GHz", "47000"},
-    {"68 GHz", "68000"},
-    {"76 GHz", "75000"},
-    {"122 GHz", "122000"},
-    {"134 GHz", "134000"},
-    {"241 GHz", "241000"}
-  ]
+  @band_options BandConfig.band_options()
 
   @mode_options ~w(CW SSB FM FT8 FT4)
 

test/microwaveprop/propagation/band_config_test.exs

@@ -3,7 +3,7 @@ defmodule Microwaveprop.Propagation.BandConfigTest do
 
   alias Microwaveprop.Propagation.BandConfig
 
-  @all_freqs [10_000, 24_000, 47_000, 68_000, 75_000, 122_000, 134_000, 241_000]
+  @all_freqs [902, 1_296, 2_304, 3_456, 5_760, 10_000, 24_000, 47_000, 68_000, 75_000, 122_000, 134_000, 241_000]
 
   describe "get/1" do
     test "returns config for 10 GHz" do
@@ -98,9 +98,9 @@ defmodule Microwaveprop.Propagation.BandConfigTest do
   end
 
   describe "all_bands/0" do
-    test "returns 8 bands" do
+    test "returns 13 bands" do
       bands = BandConfig.all_bands()
-      assert length(bands) == 8
+      assert length(bands) == 13
     end
 
     test "bands are sorted by frequency" do
@@ -275,10 +275,16 @@ defmodule Microwaveprop.Propagation.BandConfigTest do
       assert BandConfig.get(10_000).humidity_effect == :beneficial
     end
 
-    test "all other bands have harmful humidity effect" do
-      for freq <- @all_freqs -- [10_000] do
-        config = BandConfig.get(freq)
-        assert config.humidity_effect == :harmful, "#{freq} should be :harmful"
+    test "sub-10 GHz bands are beneficial, 24+ GHz are harmful" do
+      beneficial = [902, 1_296, 2_304, 3_456, 5_760, 10_000]
+      harmful = @all_freqs -- beneficial
+
+      for freq <- beneficial do
+        assert BandConfig.get(freq).humidity_effect == :beneficial, "#{freq} should be :beneficial"
+      end
+
+      for freq <- harmful do
+        assert BandConfig.get(freq).humidity_effect == :harmful, "#{freq} should be :harmful"
       end
     end
   end

test/microwaveprop/propagation_test.exs

@@ -5,7 +5,7 @@ defmodule Microwaveprop.PropagationTest do
   alias Microwaveprop.Propagation.GridScore
 
   describe "score_grid_point/4" do
-    test "scores a single point for all 8 bands" do
+    test "scores a single point for all bands" do
       hrrr_profile = %{
         surface_temp_c: 25.0,
         surface_dewpoint_c: 18.0,
@@ -25,7 +25,7 @@ defmodule Microwaveprop.PropagationTest do
       valid_time = ~U[2026-07-15 13:00:00Z]
       results = Propagation.score_grid_point(hrrr_profile, valid_time, 33.0, -97.0)
 
-      assert length(results) == 8
+      assert length(results) == 13
 
       Enum.each(results, fn result ->
         assert result.score >= 0 and result.score <= 100