CSV Imports Overhaul (Transactions, Trades, Accounts, and Mint import support) (#1209)

* Remove stale 1.0 import logic and model

* Fresh start

* Checkpoint before removing nav

* First working prototype

* Add trade, account, and mint import flows

* Basic working version with tests

* System tests for each import type

* Clean up mappings flow

* Clean up PR, refactor stale code, tests

* Add back row validations

* Row validations

* Fix import job test

* Fix import navigation

* Fix mint import configuration form

* Currency preset for new accounts

app/views/imports/_nav.html.erb

@@ -0,0 +1,40 @@
+<%# locals: (import:) %>
+
+<% steps = [
+  { name: "Upload", path: import_upload_path(import), is_complete: import.uploaded?, step_number: 1 },
+  { name: "Configure", path: import_configuration_path(import), is_complete: import.configured?, step_number: 2 },
+  { name: "Clean", path: import_clean_path(import), is_complete: import.cleaned?, step_number: 3 },
+  { name: "Map", path: import_confirm_path(import), is_complete: import.publishable?, step_number: 4 },
+  { name: "Confirm", path: import_path(import), is_complete: import.complete?, step_number: 5 }
+] %>
+
+<ul class="flex items-center gap-2">
+  <% steps.each_with_index do |step, idx| %>
+    <li class="flex items-center gap-2 group">
+      <% is_current = request.path == step[:path] %>
+
+      <% text_class = if is_current
+                  "text-gray-900"
+                else
+                  step[:is_complete] ? "text-green-600" : "text-gray-500"
+                end %>
+      <% step_class = if is_current
+                  "bg-gray-900 text-white"
+                else
+                  step[:is_complete] ? "bg-green-600/10 border-alpha-black-25" : "bg-gray-50"
+                end %>
+
+      <%= link_to step[:path], class: "flex items-center gap-3" do %>
+        <div class="flex items-center gap-2 text-sm font-medium <%= text_class %>">
+          <span class="<%= step_class %> w-7 h-7 rounded-full shrink-0 inline-flex items-center justify-center border border-transparent">
+            <%= step[:is_complete] && !is_current ? lucide_icon("check", class: "w-4 h-4") : idx + 1 %>
+          </span>
+
+          <span><%= step[:name] %></span>
+        </div>
+      <% end %>
+
+      <div class="h-px bg-alpha-black-200 w-12 group-last:hidden"></div>
+    </li>
+  <% end %>
+</ul>