fix(a11y): underline the new cross-links and give the chart link a touch target

The integrations/source-priority hint links relied on colour alone and
the chart's adjust-targets link measured sixteen pixels tall on mobile —
both caught by the e2e gate. The links carry a permanent underline now
and the chart link a full-height touch area.

src/components/charts/health-chart.tsx

@@ -1482,7 +1482,7 @@ export function HealthChart({
               <Link
                 href={targetSettingsHref}
                 data-slot="chart-target-settings-link"
-                className="text-muted-foreground hover:text-foreground inline-flex items-center gap-1 text-xs underline-offset-2 transition-colors hover:underline"
+                className="text-muted-foreground hover:text-foreground inline-flex min-h-11 items-center gap-1 text-xs underline underline-offset-2 transition-colors sm:min-h-9"
               >
                 <SlidersHorizontal className="h-3 w-3" aria-hidden="true" />
                 {t("charts.adjustTargets")}

src/components/settings/integrations-section.tsx

@@ -272,7 +272,7 @@ export function IntegrationsSection() {
           {t("settings.integrationsSourcesHint")}{" "}
           <Link
             href="/settings/sources"
-            className="text-primary underline-offset-2 hover:underline"
+            className="text-primary underline underline-offset-2"
             data-slot="integrations-sources-cross-link"
           >
             {t("settings.integrationsSourcesHintLink")}

src/components/settings/sources-section.tsx

@@ -314,7 +314,7 @@ export function SourcesSection() {
           {t("settings.sections.sources.integrationsHint")}{" "}
           <Link
             href="/settings/integrations"
-            className="text-primary underline-offset-2 hover:underline"
+            className="text-primary underline underline-offset-2"
             data-slot="sources-integrations-cross-link"
           >
             {t("settings.sections.sources.integrationsHintLink")}