feat: Enhance currency handling and validation across scenarios

- Updated form template to prefill currency input with default value and added help text for clarity.
- Modified integration tests to assert more descriptive error messages for invalid currency codes.
- Introduced new tests for currency normalization and validation in various scenarios, including imports and exports.
- Added comprehensive tests for pricing calculations, ensuring defaults are respected and overrides function correctly.
- Implemented unit tests for pricing settings repository, ensuring CRUD operations and default settings are handled properly.
- Enhanced scenario pricing evaluation tests to validate currency handling and metadata defaults.
- Added simulation tests to ensure Monte Carlo runs are accurate and handle various distribution scenarios.

templates/partials/reports_header.html

@@ -0,0 +1,24 @@
+<header class="page-header">
+  <div>
+    <h1 class="page-title">{{ title }}</h1>
+    {% if subtitle %}
+      <p class="page-subtitle">{{ subtitle }}</p>
+    {% endif %}
+  </div>
+  {% if actions %}
+    <div class="page-actions">
+      {% for action in actions %}
+        {% set classes = action.classes or 'button button-secondary' %}
+        <a
+          href="{{ action.href }}"
+          class="{{ classes }}"
+          {% if action.target %}target="{{ action.target }}"{% endif %}
+          {% if action.rel %}rel="{{ action.rel }}"{% endif %}
+          {% if action.download %}download="{{ action.download }}"{% endif %}
+        >
+          {{ action.label }}
+        </a>
+      {% endfor %}
+    </div>
+  {% endif %}
+</header>