implement demo mode

src/shims/demo.js

@@ -0,0 +1,61 @@
+// Client-side demo mode hooks.
+//
+// Detects demo mode via the body data attribute the server stamps in buildIndexHtml.
+// Pre-trusts vaults so Obsidian skips its first-run "Trust author" dialog, and bridges no-vault landing to /api/demo/provision.
+
+export function isDemoMode() {
+  return (
+    typeof document !== "undefined" &&
+    document.body &&
+    document.body.dataset.demoMode === "true"
+  );
+}
+
+// Demo vaults are provisioned from our own template, never from an unknown source.
+export function autoTrustDemoVaults(vaultList) {
+  if (!isDemoMode() || !Array.isArray(vaultList)) {
+    return;
+  }
+
+  for (const v of vaultList) {
+    if (v && v.id) {
+      localStorage.setItem("enable-plugin-" + v.id, "true");
+    }
+  }
+}
+
+// In demo mode with no vault selected, ask the server to provision one and reload at ?vault=<name>.
+// Sync XHR so we block before Obsidian boots. Returns true if navigation is in progress (caller should halt init).
+export function maybeProvisionDemoVault() {
+  if (!isDemoMode()) {
+    return false;
+  }
+
+  const urlParams = new URLSearchParams(window.location.search);
+
+  if (urlParams.get("vault")) {
+    return false;
+  }
+
+  try {
+    const xhr = new XMLHttpRequest();
+
+    xhr.open("GET", "/api/demo/provision", false);
+    xhr.send();
+
+    if (xhr.status === 200) {
+      const { vault } = JSON.parse(xhr.responseText);
+
+      if (vault) {
+        // Pre-trust before redirect.
+        localStorage.setItem("enable-plugin-" + vault, "true");
+        window.location.replace("/?vault=" + encodeURIComponent(vault));
+        return true;
+      }
+    }
+  } catch (e) {
+    console.warn("[ignis] Demo provision failed:", e);
+  }
+
+  return false;
+}

src/shims/init.js

@@ -9,6 +9,7 @@ import {
   initWorkspacePatch,
 } from "./workspace.js";
 import { prefetchVaultContent } from "./fs/indexer-prefetch.js";
+import { autoTrustDemoVaults, maybeProvisionDemoVault } from "./demo.js";
 
 function resolveVaultId() {
   const urlParams = new URLSearchParams(window.location.search);
@@ -213,6 +214,10 @@ function initCoreSyncGuardFallback() {
 }
 
 export function initialize() {
+  if (maybeProvisionDemoVault()) {
+    return;
+  }
+
   resolveVaultId();
   resolveWorkspaceName();
   loadPresetIfRequested();
@@ -222,6 +227,7 @@ export function initialize() {
   if (bootstrap) {
     applyVaultInfo(bootstrap.vault);
     window.__vaultList = bootstrap.vaultList;
+    autoTrustDemoVaults(bootstrap.vaultList);
     applyTree(bootstrap.tree);
     applyCoreSyncGuard(bootstrap.plugins);