keys: n walks the search results, and a half-typed key shows

`n` / `N` move to the next / previous search result and open it beside the
results, so the next `n` goes on from there; a folder is only highlighted,
as going into it would end the search. Past the last result it starts
again at the first and says so, as vim's `wrapscan` does. Clearing the
search is left to `:noh` / `:clear`, as in vim, rather than to `n`.

After `g`, `d`, `]` or `[` the status line shows the key waiting for its
second half, like vim's `showcmd`, and forgets it after a second.

web/src/App.svelte

@@ -44,6 +44,7 @@
   let importRoot = false
   let shell = $state<HTMLDivElement>()
   let overlayEl = $state<HTMLDivElement>()
+  /** The first half of `gg`, `dd`, `]]` …, shown until the second comes. */
   let pending = $state('')
   /** `F`: the pane whose links and buttons are wearing hints right now. */
   let hintRoot = $state<HTMLElement | null>(null)
@@ -135,6 +136,13 @@
     return () => clearTimeout(timer)
   })
 
+  // A first half left alone is forgotten, as vim's `timeoutlen` does.
+  $effect(() => {
+    if (!pending) return
+    const timer = setTimeout(() => (pending = ''), 1000)
+    return () => clearTimeout(timer)
+  })
+
   // Guard against losing a half-written entry to a stray refresh.
   $effect(() => {
     if (!workspace.dirty) return
@@ -775,8 +783,11 @@
         })()
         break
       case 'n':
+      case 'N':
+        // Through the results, as vim's `n` goes through the matches; the
+        // search itself stays until `:noh`.
         event.preventDefault()
-        if (workspace.query) void workspace.guard(() => workspace.search(''))
+        void workspace.guard(() => workspace.nextResult(key === 'n' ? 1 : -1))
         break
       case '/':
         event.preventDefault()
@@ -864,7 +875,7 @@
       {/key}
     </main>
 
-    <StatusBar />
+    <StatusBar {pending} />
 
     {#if cmdline !== null}
       <CommandLine initial={cmdline} global={cmdGlobal} close={() => ((cmdline = null), (cmdGlobal = false))} />