chat history panel keyed (344 -> 283)

Three module-level tab/option tables carried labels, so they carry labelKey now and
the components resolve them.

The hidden-subfolder hint hand-rolled a plural with a ternary ("one is" / "ones are"),
which is a real plural entry now — verified at 0, 1 and 2 in both locales.

OpenCode and Claude are product names, wrapped rather than keyed.

Scanner: the jsx-text pattern now rejects a preceding `=`, so an arrow return type is
not read as prose — `(id: string) => Promise<unknown>` was being reported as the string
"Promise", seven times across the panels. Verified the delta is exactly those seven.

scripts/i18n/scan-hardcoded.ts

@@ -52,7 +52,10 @@ const Q = String.raw`(?:"([^"\n]{2,120})"|'([^'\n]{2,120})')`;
  */
 const PATTERNS: { kind: string; rx: RegExp; neverTranslate?: true }[] = [
   // >Some visible words<
-  { kind: 'jsx text', rx: />\s*([A-Z][A-Za-z0-9][^<>{}\n]{2,100}?)\s*</g },
+  //
+  // The lookbehind rejects `=>`, so an arrow return type does not read as JSX text: `(id: string) =>
+  // Promise<unknown>` was reported as the string "Promise".
+  { kind: 'jsx text', rx: /(?<!=)>\s*([A-Z][A-Za-z0-9][^<>{}\n]{2,100}?)\s*</g },
   // placeholder="..." and friends
   {
     kind: 'attributes',