feat(backend,frontend): search everywhere in buttons, links and message data, a jump from search or an alert lights up the found words and buttons

frontend/src/lib/components/InlineButtons.svelte

@@ -1,13 +1,15 @@
 <script lang="ts">
   import type { InlineButton } from "#lib/api/types.js";
+  import { buttonHasMark } from "#lib/format/search.js";
   import { safeHref } from "#lib/format/url.js";
   import { t } from "#lib/i18n/locale.svelte.js";
 
   interface Props {
+    marks?: string[];
     rows: InlineButton[][];
   }
 
-  let { rows }: Props = $props();
+  let { marks = [], rows }: Props = $props();
 
   let copied = $state<string | null>(null);
   let resetTimer: ReturnType<typeof setTimeout> | undefined;
@@ -27,12 +29,14 @@
     <div class="row">
       {#each row as button, colIndex (colIndex)}
         {@const key = `${rowIndex}:${colIndex}`}
+        {@const lit = marks.length > 0 && buttonHasMark(button, marks)}
         {#if button.kind === "url" && button.url}
           <a
             class="button"
             href={safeHref(button.url)}
             rel="noopener"
             target="_blank"
+            class:found={lit}
           >
             <span class="label">{button.text}</span>
             <span class="corner">↗</span>
@@ -42,13 +46,14 @@
             class="button"
             onclick={() => copy(key, button.data ?? "")}
             type="button"
+            class:found={lit}
           >
             <span class="label"
               >{copied === key ? t("inline.copied") : button.text}</span
             >
           </button>
         {:else}
-          <span class="button static">
+          <span class="button static" class:found={lit}>
             <span class="label">{button.text}</span>
           </span>
         {/if}
@@ -104,6 +109,27 @@
     }
   }
 
+  .found {
+    animation: found-flash 3s ease;
+  }
+
+  @keyframes found-flash {
+    0%,
+    70% {
+      background-color: color-mix(
+        in srgb,
+        var(--color-primary) 30%,
+        var(--color-message-reaction)
+      );
+      box-shadow: inset 0 0 0 1px var(--color-primary);
+    }
+
+    100% {
+      background-color: var(--color-message-reaction);
+      box-shadow: inset 0 0 0 1px transparent;
+    }
+  }
+
   .label {
     overflow: hidden;
     text-overflow: ellipsis;