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/cssstyle/lib/properties/border.js

@@ -0,0 +1,42 @@
+"use strict";
+
+const parsers = require("../parsers");
+const borderWidth = require("./borderWidth");
+const borderStyle = require("./borderStyle");
+const borderColor = require("./borderColor");
+
+const shorthandFor = new Map([
+  ["border-width", borderWidth],
+  ["border-style", borderStyle],
+  ["border-color", borderColor]
+]);
+
+module.exports.definition = {
+  set(v) {
+    v = parsers.prepareValue(v, this._global);
+    if (/^none$/i.test(v)) {
+      v = "";
+    }
+    if (parsers.hasVarFunc(v)) {
+      for (const [key] of shorthandFor) {
+        this._setProperty(key, "");
+      }
+      this._setProperty("border", v);
+    } else {
+      this._midShorthandSetter("border", v, shorthandFor, ["top", "right", "bottom", "left"]);
+    }
+  },
+  get() {
+    let val = this.getPropertyValue("border");
+    if (parsers.hasVarFunc(val)) {
+      return val;
+    }
+    val = this._shorthandGetter("border", shorthandFor);
+    if (parsers.hasVarFunc(val)) {
+      return "";
+    }
+    return val;
+  },
+  enumerable: true,
+  configurable: true
+};