Refactor error handling, client, and tests for Ollama integration

jest.setup.js

@@ -0,0 +1,70 @@
+// jest.setup.js
+
+// Setup global browser APIs not provided by jsdom
+
+// Mock confirm/alert
+global.confirm = jest.fn().mockReturnValue(true);
+global.alert = jest.fn();
+
+// Mock fetch as a global no-op that can be overridden per-test
+global.fetch = jest.fn();
+
+// Ensure TextEncoder/TextDecoder are available (Node.js polyfill)
+const { TextEncoder, TextDecoder } = require('util');
+global.TextEncoder = TextEncoder;
+global.TextDecoder = TextDecoder;
+
+// Ensure AbortController/AbortSignal are available
+if (!global.AbortController) {
+  global.AbortController = class AbortController {
+    constructor() {
+      this.signal = {
+        aborted: false,
+        addEventListener: jest.fn(),
+        removeEventListener: jest.fn(),
+        dispatchEvent: jest.fn(),
+        throwIfAborted: () => {},
+      };
+    }
+    abort() {
+      this.signal.aborted = true;
+    }
+  };
+}
+
+// Extend HTMLElement with Obsidian-style createEl helper
+// This allows test elements to create children just like Obsidian's DOM API
+if (typeof HTMLElement !== 'undefined') {
+  HTMLElement.prototype.createEl = function (tag, options) {
+    const el = document.createElement(tag);
+    if (options) {
+      if (options.cls) {
+        const classes = Array.isArray(options.cls) ? options.cls : options.cls.split(' ');
+        classes.forEach((c) => {
+          if (c) el.classList.add(c);
+        });
+      }
+      if (options.text) {
+        el.textContent = options.text;
+      }
+      if (options.html) {
+        el.innerHTML = options.html;
+      }
+      if (options.attr) {
+        Object.entries(options.attr).forEach(([k, v]) => {
+          el.setAttribute(k, v);
+        });
+      }
+      if (options.prop) {
+        Object.entries(options.prop).forEach(([k, v]) => {
+          el[k] = v;
+        });
+      }
+      if (options.select) {
+        options.select(el);
+      }
+    }
+    this.appendChild(el);
+    return el;
+  };
+}