Cans UI + parity: unlock-cookie flow, /can page, listings badge, custom slug, delete, sweeper; #32 perf notes (#4, #32)

internal/web/templates/can.html

@@ -0,0 +1,36 @@
+{{template "head" .}}
+{{template "topbar" .}}
+<div class="center">
+  <div class="float can-page" style="max-width:900px; width:100%;">
+    <div class="inner">
+      <h1>{{.Title}} <span class="badge" title="This is a can — a bundle of pastes">can</span></h1>
+      {{if .HasDescription}}<p class="sub">{{.Description}}</p>{{end}}
+      <p class="hint">{{.ItemCount}} item{{if ne .ItemCount 1}}s{{end}} · {{.SizeHuman}} · created <span data-ts="{{.CreatedAtUnix}}">{{.CreatedAgo}}</span>{{if .ExpiresAt}} · expires in {{.ExpiresIn}}{{end}}{{if .HasPassword}} · password protected{{end}}</p>
+
+      <div class="can-items">
+        {{range .Items}}
+        <div class="can-item float">
+          <div class="can-item-head">
+            <strong>{{.Title}}</strong>
+            <span class="dim">{{.Size}}</span>
+            {{if .IsFile}}
+              <a class="btn btn-icon" href="/api/cans/{{$.ID}}/items/{{.ID}}" download="{{.Title}}" title="Download file" aria-label="Download {{.Title}}">↓</a>
+            {{else}}
+              <a class="btn btn-icon" href="/api/cans/{{$.ID}}/items/{{.ID}}" title="Raw item" aria-label="Raw {{.Title}}">⧉</a>
+            {{end}}
+          </div>
+          {{if not .IsFile}}
+          <details class="can-item-body">
+            <summary>Show content</summary>
+            <pre class="code"><code>{{.ContentHTML}}</code></pre>
+          </details>
+          {{else}}
+          <div class="hint">Attached file — use the download button above.</div>
+          {{end}}
+        </div>
+        {{end}}
+      </div>
+    </div>
+  </div>
+</div>
+{{template "foot" .}}