feat(frontend): add API client, layout, and routing

- Create Axios-based API client with sources, jobs, and dashboard endpoints
- Add responsive Layout component with navigation sidebar
- Set up React Router with Dashboard, Backups, and Settings routes
- Configure TanStack Query provider with default options
- Use lucide-react for navigation icons

frontend/node_modules/rrweb-cssom/lib/CSSKeyframesRule.js

@@ -0,0 +1,39 @@
+//.CommonJS
+var CSSOM = {
+	CSSRule: require("./CSSRule").CSSRule
+};
+///CommonJS
+
+
+/**
+ * @constructor
+ * @see http://www.w3.org/TR/css3-animations/#DOM-CSSKeyframesRule
+ */
+CSSOM.CSSKeyframesRule = function CSSKeyframesRule() {
+	CSSOM.CSSRule.call(this);
+	this.name = '';
+	this.cssRules = [];
+};
+
+CSSOM.CSSKeyframesRule.prototype = new CSSOM.CSSRule();
+CSSOM.CSSKeyframesRule.prototype.constructor = CSSOM.CSSKeyframesRule;
+CSSOM.CSSKeyframesRule.prototype.type = 7;
+//FIXME
+//CSSOM.CSSKeyframesRule.prototype.insertRule = CSSStyleSheet.prototype.insertRule;
+//CSSOM.CSSKeyframesRule.prototype.deleteRule = CSSStyleSheet.prototype.deleteRule;
+
+// http://www.opensource.apple.com/source/WebCore/WebCore-955.66.1/css/WebKitCSSKeyframesRule.cpp
+Object.defineProperty(CSSOM.CSSKeyframesRule.prototype, "cssText", {
+  get: function() {
+    var cssTexts = [];
+    for (var i=0, length=this.cssRules.length; i < length; i++) {
+      cssTexts.push("  " + this.cssRules[i].cssText);
+    }
+    return "@" + (this._vendorPrefix || '') + "keyframes " + this.name + " { \n" + cssTexts.join("\n") + "\n}";
+  }
+});
+
+
+//.CommonJS
+exports.CSSKeyframesRule = CSSOM.CSSKeyframesRule;
+///CommonJS