Add form styles and update button classes for consistency

- Introduced a new CSS file for form styles (forms.css) to enhance form layout and design.
- Removed deprecated button styles from imports.css and updated button classes across templates to use the new utility classes.
- Updated various templates to reflect the new button styles, ensuring a consistent look and feel throughout the application.
- Refactored form-related styles in main.css and removed redundant styles from projects.css and scenarios.css.
- Ensured responsive design adjustments for form actions in smaller viewports.

static/css/scenarios.css

@@ -120,63 +120,6 @@
   margin: 0;
 }
 
-.scenario-form .form-grid {
-  display: grid;
-  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
-  gap: 1.25rem;
-}
-
-.scenario-form .form-group {
-  display: flex;
-  flex-direction: column;
-  gap: 0.5rem;
-}
-
-.scenario-form .form-group label {
-  font-weight: 600;
-  color: var(--text);
-}
-
-.scenario-form .form-group input,
-.scenario-form .form-group select,
-.scenario-form .form-group textarea {
-  padding: 0.75rem 0.85rem;
-  border-radius: var(--radius-sm);
-  border: 1px solid var(--card-border);
-  background: rgba(8, 12, 19, 0.78);
-  color: var(--text);
-}
-
-.scenario-form .form-group textarea {
-  resize: vertical;
-}
-
-.scenario-form .form-group input:focus,
-.scenario-form .form-group select:focus,
-.scenario-form .form-group textarea:focus {
-  outline: 2px solid var(--brand-2);
-  outline-offset: 1px;
-}
-
-.form-group--error input,
-.form-group--error select,
-.form-group--error textarea {
-  border-color: rgba(209, 75, 75, 0.6);
-  box-shadow: 0 0 0 1px rgba(209, 75, 75, 0.3);
-}
-
-.field-help {
-  margin: 0;
-  font-size: 0.85rem;
-  color: var(--color-text-subtle);
-}
-
-.field-error {
-  margin: 0;
-  font-size: 0.85rem;
-  color: var(--danger);
-}
-
 .table-responsive {
   width: 100%;
   overflow-x: auto;
@@ -396,7 +339,7 @@
   flex-wrap: wrap;
 }
 
-.scenario-item__actions .btn-link {
+.scenario-item__actions .btn--link {
   padding: 0;
 }