fix: resolve CSP and accessibility issues (#60)

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Co-authored-by: Hikari <hikari@nhcarrigan.com>
Reviewed-on: #60

apps/frontend/src/app/app.scss

@@ -1,3 +1,35 @@
+// Skip to main content link - visually hidden but accessible to screen readers
+.skip-link {
+  position: absolute !important;
+  width: 1px !important;
+  height: 1px !important;
+  padding: 0 !important;
+  margin: -1px !important;
+  overflow: hidden !important;
+  clip: rect(0, 0, 0, 0) !important;
+  white-space: nowrap !important;
+  border: 0 !important;
+}
+
+.skip-link:focus {
+  position: fixed !important;
+  top: 0 !important;
+  left: 0 !important;
+  width: auto !important;
+  height: auto !important;
+  padding: 0.75rem 1.5rem !important;
+  margin: 0 !important;
+  overflow: visible !important;
+  clip: auto !important;
+  white-space: normal !important;
+  background: var(--witch-rose) !important;
+  color: var(--witch-moon) !important;
+  text-decoration: none !important;
+  font-weight: 600 !important;
+  border-radius: 0 0 4px 0 !important;
+  z-index: 10000 !important;
+}
+
 .main-content {
   min-height: calc(100vh - 60px); // Assuming header is ~60px
   background-color: transparent; // Let the body background show through