feat(ui): add breadcrumb icons, fix alignment, and remove duplicate form headers

- add section icons to all breadcrumbs across every page
- fix breadcrumb nav display:flex so icons align vertically with buttons
- wrap all page breadcrumbs in pageToolbar div for consistent layout
- add Breadcrumbs to AllRunsPage which previously used a plain h1
- fix envCardHeader flex:1 so settings button hugs the right edge
- remove card header from environment create/edit forms (duplicated breadcrumb)

client/src/ui/Input/Input.module.css

@@ -23,6 +23,7 @@
   height: 36px;
   width: 100%;
   outline: none;
+  box-shadow: var(--shadow-xs);
   transition: border-color var(--transition), box-shadow var(--transition);
 }