Tweaks (#24484)

* fix long press on mobile in face and classification

the listener was on the image only, so long pressing on any overlaid div/text area would cause iOS to select the text instead of adding the blue outline

* improve navigation to and from explore

when viewing a tracked object in explore from a classification card, triggers, or the detail stream, explore would open and show a single tracked object. on mobile (noted especially on iOS with frigate in HA), there is no obvious way to navigate back, so add a back button in its usual spot.

also, when going back to the classification view from explore, it may not be obvious which thumbnail you were last viewing, so add a temporary blue outline around the card like review and explore already does

* test tweaks

web/e2e/specs/explore.spec.ts

@@ -216,6 +216,18 @@ test.describe("Explore — content @high", () => {
 // Similarity search URL param
 // ---------------------------------------------------------------------------
 
+test.describe("Explore: back button @high", () => {
+  test("direct visits do not show a back button", async ({ frigateApp }) => {
+    await frigateApp.goto("/explore?labels=person");
+    await expect(frigateApp.page.getByLabel("Labels").first()).toBeVisible({
+      timeout: 10_000,
+    });
+    await expect(
+      frigateApp.page.getByRole("button", { name: "Go back" }),
+    ).toHaveCount(0);
+  });
+});
+
 test.describe("Explore — similarity search (desktop) @high", () => {
   test.skip(
     ({ frigateApp }) => frigateApp.isMobile,