Fix three security issues

1. Prevent user_id impersonation in contact submissions
   - Remove user_id from submission_changeset cast fields
   - Pass user_id as a separate server-side argument to create_contact/2
   - Client form params can no longer forge account-linked contacts

2. Restrict flag toggle to admins only
   - Add admin? guard to toggle_flag event handler
   - Hide flag button from non-admin users in template

3. Reset enrichment on timestamp edits
   - Add qso_timestamp to the fields that trigger enrichment reset
   - Prevents stale weather/HRRR/IEMRE data after time changes

lib/microwaveprop/radio.ex

@@ -387,10 +387,13 @@ defmodule Microwaveprop.Radio do
 
   @dedup_window_seconds 3600
 
-  @spec create_contact(map()) ::
+  @spec create_contact(map(), String.t() | nil) ::
           {:ok, Contact.t()} | {:error, Ecto.Changeset.t()} | {:error, :duplicate, Contact.t()}
-  def create_contact(attrs) do
-    changeset = Contact.submission_changeset(%Contact{}, attrs)
+  def create_contact(attrs, user_id \\ nil) do
+    changeset =
+      %Contact{}
+      |> Contact.submission_changeset(attrs)
+      |> maybe_put_user_id(user_id)
 
     if changeset.valid? do
       insert_validated_contact(changeset)
@@ -399,6 +402,9 @@ defmodule Microwaveprop.Radio do
     end
   end
 
+  defp maybe_put_user_id(changeset, nil), do: changeset
+  defp maybe_put_user_id(changeset, user_id), do: Ecto.Changeset.put_change(changeset, :user_id, user_id)
+
   defp insert_validated_contact(changeset) do
     if existing = find_duplicate_contact(changeset) do
       {:error, :duplicate, existing}
@@ -632,12 +638,13 @@ defmodule Microwaveprop.Radio do
   end
 
   defp maybe_recompute_positions(changes, contact, proposed) do
-    grids_or_band_changed =
+    needs_recompute =
       Map.has_key?(proposed, "grid1") or
         Map.has_key?(proposed, "grid2") or
-        Map.has_key?(proposed, "band")
+        Map.has_key?(proposed, "band") or
+        Map.has_key?(proposed, "qso_timestamp")
 
-    if grids_or_band_changed do
+    if needs_recompute do
       recompute_positions(changes, contact, proposed)
     else
       changes

lib/microwaveprop/radio/contact.ex

@@ -59,7 +59,7 @@ defmodule Microwaveprop.Radio.Contact do
     |> validate_required(@required_fields)
   end
 
-  @submission_fields ~w(station1 station2 qso_timestamp mode band grid1 grid2 submitter_email user_id)a
+  @submission_fields ~w(station1 station2 qso_timestamp mode band grid1 grid2 submitter_email)a
   @submission_required ~w(station1 station2 qso_timestamp mode band grid1 grid2)a
   @allowed_modes ~w(CW SSB FM FT8 FT4 Q65)
   @allowed_bands Enum.map(~w(1296 2304 3456 5760 10000 24000 47000 68000 75000 122000 134000 241000), &Decimal.new/1)

lib/microwaveprop_web/live/contact_live/show.ex

@@ -122,8 +122,12 @@ defmodule MicrowavepropWeb.ContactLive.Show do
   end
 
   def handle_event("toggle_flag", _params, socket) do
-    contact = Radio.toggle_flagged_invalid!(socket.assigns.contact)
-    {:noreply, assign(socket, contact: contact)}
+    if admin?(socket.assigns.current_scope) do
+      contact = Radio.toggle_flagged_invalid!(socket.assigns.contact)
+      {:noreply, assign(socket, contact: contact)}
+    else
+      {:noreply, put_flash(socket, :error, "Admins only.")}
+    end
   end
 
   def handle_event("toggle_profile", %{"id" => id}, socket) do
@@ -575,6 +579,7 @@ defmodule MicrowavepropWeb.ContactLive.Show do
             </button>
           <% end %>
           <button
+            :if={admin?(assigns)}
             phx-click="toggle_flag"
             class={[
               "btn btn-sm",

lib/microwaveprop_web/live/submit_live.ex

@@ -76,9 +76,9 @@ defmodule MicrowavepropWeb.SubmitLive do
     if recently_submitted?(socket) do
       {:noreply, put_flash(socket, :error, "Please wait before submitting another contact.")}
     else
-      contact_params = merge_user_params(contact_params, socket)
+      {contact_params, user_id} = merge_user_params(contact_params, socket)
 
-      case Radio.create_contact(contact_params) do
+      case Radio.create_contact(contact_params, user_id) do
         {:ok, contact} ->
           ContactWeatherEnqueueWorker.enqueue_for_contact(contact)
 
@@ -217,12 +217,10 @@ defmodule MicrowavepropWeb.SubmitLive do
   defp merge_user_params(params, socket) do
     case current_user(socket.assigns) do
       %{id: user_id, email: user_email} ->
-        params
-        |> Map.put("user_id", user_id)
-        |> Map.put("submitter_email", user_email)
+        {Map.put(params, "submitter_email", user_email), user_id}
 
       _ ->
-        params
+        {params, nil}
     end
   end