feat: add server-side session filtering with input bytes and human score

Replace client-side session table filtering with server-side filtering
via a new /fragments/recent-sessions htmx endpoint. Add InputBytes column
to session tables, Human score > 0 checkbox filter, and Sort by Input
Bytes option to help identify sessions with actual shell interaction.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

internal/web/templates/dashboard.html

@@ -13,6 +13,10 @@
             <label>Country <input type="text" name="country" placeholder="CN" maxlength="2"></label>
             <label>Username <input type="text" name="username" placeholder="root"></label>
         </div>
+        <div class="grid">
+            <label><input type="checkbox" name="human_score" value="1"> Human score &gt; 0</label>
+            <label>Sort by <select name="sort"><option value="connected_at">Recent</option><option value="input_bytes">Input Bytes</option></select></label>
+        </div>
         <button type="submit">Apply</button>
         <button type="button" class="secondary" onclick="clearFilters()">Clear</button>
     </form>
@@ -61,25 +65,13 @@
                 <th>Username</th>
                 <th>Type</th>
                 <th>Score</th>
+                <th>Input</th>
                 <th>Connected</th>
                 <th>Disconnected</th>
             </tr>
         </thead>
         <tbody>
-            {{range .RecentSessions}}
-            <tr>
-                <td><a href="/sessions/{{.ID}}"><code>{{truncateID .ID}}</code></a>{{if gt .EventCount 0}} <mark>replay</mark>{{end}}</td>
-                <td>{{.IP}}</td>
-                <td>{{.Country}}</td>
-                <td>{{.Username}}</td>
-                <td>{{if .ExecCommand}}<mark>exec</mark>{{else}}{{.ShellName}}{{end}}</td>
-                <td>{{if .HumanScore}}{{if gt (derefFloat .HumanScore) 0.6}}<mark>{{formatScore .HumanScore}}</mark>{{else}}{{formatScore .HumanScore}}{{end}}{{else}}-{{end}}</td>
-                <td>{{formatTime .ConnectedAt}}</td>
-                <td>{{if .DisconnectedAt}}{{formatTime (derefTime .DisconnectedAt)}}{{else}}<mark>active</mark>{{end}}</td>
-            </tr>
-            {{else}}
-            <tr><td colspan="8">No sessions</td></tr>
-            {{end}}
+            {{template "recent_sessions" .RecentSessions}}
         </tbody>
     </table>
 </section>

internal/web/templates/fragments/active_sessions.html

@@ -8,6 +8,7 @@
             <th>Username</th>
             <th>Type</th>
             <th>Score</th>
+            <th>Input</th>
             <th>Connected</th>
         </tr>
     </thead>
@@ -20,10 +21,11 @@
             <td>{{.Username}}</td>
             <td>{{if .ExecCommand}}<mark>exec</mark>{{else}}{{.ShellName}}{{end}}</td>
             <td>{{if .HumanScore}}{{if gt (derefFloat .HumanScore) 0.6}}<mark>{{formatScore .HumanScore}}</mark>{{else}}{{formatScore .HumanScore}}{{end}}{{else}}-{{end}}</td>
+            <td>{{formatBytes .InputBytes}}</td>
             <td>{{formatTime .ConnectedAt}}</td>
         </tr>
         {{else}}
-        <tr><td colspan="7">No active sessions</td></tr>
+        <tr><td colspan="8">No active sessions</td></tr>
         {{end}}
     </tbody>
 </table>

internal/web/templates/fragments/recent_sessions.html

@@ -0,0 +1,17 @@
+{{define "recent_sessions"}}
+{{range .}}
+<tr>
+    <td><a href="/sessions/{{.ID}}"><code>{{truncateID .ID}}</code></a>{{if gt .EventCount 0}} <mark>replay</mark>{{end}}</td>
+    <td>{{.IP}}</td>
+    <td>{{.Country}}</td>
+    <td>{{.Username}}</td>
+    <td>{{if .ExecCommand}}<mark>exec</mark>{{else}}{{.ShellName}}{{end}}</td>
+    <td>{{if .HumanScore}}{{if gt (derefFloat .HumanScore) 0.6}}<mark>{{formatScore .HumanScore}}</mark>{{else}}{{formatScore .HumanScore}}{{end}}{{else}}-{{end}}</td>
+    <td>{{formatBytes .InputBytes}}</td>
+    <td>{{formatTime .ConnectedAt}}</td>
+    <td>{{if .DisconnectedAt}}{{formatTime (derefTime .DisconnectedAt)}}{{else}}<mark>active</mark>{{end}}</td>
+</tr>
+{{else}}
+<tr><td colspan="9">No sessions</td></tr>
+{{end}}
+{{end}}