feat: highlight search matches and document the working UI

apps/desktop/README.md

@@ -104,3 +104,19 @@ The local clipboard report excludes queries, paths, filenames, snippets and erro
 strings. It captures available model/device/thread/runtime context without
 guessing missing values. Histories are bounded and dropped counts remain visible.
 Clipboard failure is explicit; no diagnostic telemetry is uploaded.
+
+## Reproducible documentation capture
+
+The optional loopback harness in `tools/desktop-capture` serves this production-built
+frontend against the actual shared Rust search engine and local Google model.
+Browser activation requires explicit `?capture=1`, a loopback HTTP origin and a
+ready `readme-capture` bootstrap with an ephemeral nonce. Read-only search/status
+commands use authenticated same-origin requests; indexed media uses restricted
+fixture URLs. Indexing, dialogs, external opening and resource-setting mutations
+are disabled. Ordinary browser previews remain disconnected and native Tauri
+invocations/media URLs retain their existing implementation.
+
+These documentation images show browser-rendered application content backed by
+real engine queries. They do not establish native OS chrome, global shortcuts,
+native playback or desktop interaction QA. The harness returns no mocked search
+results or replayed model output.