fix(settings): unify threshold page naming

The thresholds settings route was carrying three different
names: nav label "Personal targets", page header "Personal
targets", inner card header "Personal thresholds". The URL
slug is `/settings/thresholds`, so settled on "Personal
thresholds" everywhere in EN; DE keeps the established
"Persönliche Zielwerte". While here, dropped the duplicate
title + subtitle inside the editor card — the page-level
header already provides them and the second copy was just
visual noise.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

messages/en.json

@@ -1064,7 +1064,7 @@
         "description": "Tile layout and order."
       },
       "thresholds": {
-        "title": "Personal targets",
+        "title": "Personal thresholds",
         "description": "Override target ranges for every metric."
       },
       "ai": {

src/components/settings/thresholds-editor-section.tsx

@@ -123,10 +123,17 @@ export function ThresholdsEditorSection({ id }: { id: string }) {
       id={id}
       className="bg-card border-border scroll-mt-28 space-y-5 rounded-xl border p-6"
     >
+      {/* v1.4.19 A8 / F-07: page header `settings.sections.thresholds.*`
+          already provides the title + description for this route, so the
+          card-level title + subtitle were a duplicate of the page header.
+          Keep the icon + reset action so the card still has a visible
+          control affordance. */}
       <div className="flex items-center justify-between">
         <div className="flex items-center gap-2">
-          <SlidersHorizontal className="text-primary h-5 w-5" />
-          <h2 className="text-lg font-semibold">{t("thresholds.title")}</h2>
+          <SlidersHorizontal
+            className="text-primary h-5 w-5"
+            aria-hidden="true"
+          />
         </div>
         {data && Object.keys(data.overrides).length > 0 && (
           <Button
@@ -140,9 +147,6 @@ export function ThresholdsEditorSection({ id }: { id: string }) {
           </Button>
         )}
       </div>
-      <p className="text-muted-foreground text-sm">
-        {t("thresholds.subtitle")}
-      </p>
 
       {isLoading || !data ? (
         <div className="text-muted-foreground flex items-center gap-2 text-sm">