feat: multiple UI improvements, font settings, and memory file display names (#175)

## Summary

- **fix**: `show_thinking_blocks` setting now persists across sessions — it was defined on the TypeScript side but missing from the Rust `HikariConfig` struct, so serde silently dropped it on every save/load
- **feat**: Tool calls are now rendered as collapsible blocks matching the Extended Thinking block aesthetic, replacing the old inline dropdown approach
- **feat**: Add configurable max output tokens setting
- **feat**: Use random creative names for conversation tabs
- **test**: Significantly expanded frontend unit test coverage
- **docs**: Require tests for all changes in CLAUDE.md
- **feat**: Allow users to specify a custom terminal font (Closes #176)
- **feat**: Display friendly names for memory files derived from the first heading (Closes #177)
- **feat**: Add custom UI font support for the app chrome (buttons, labels, tabs)
- **fix**: Apply custom UI font to the full app interface — `.app-container` was hardcoded, blocking inheritance from `body`; also renamed "Custom Font" to "Custom Terminal Font" for clarity

✨ This PR was created with help from Hikari~ 🌸

Reviewed-on: #175
Co-authored-by: Hikari <hikari@nhcarrigan.com>
Co-committed-by: Hikari <hikari@nhcarrigan.com>

src/lib/stores/historyRestore.test.ts

@@ -0,0 +1,72 @@
+import { describe, it, expect, beforeEach } from "vitest";
+import {
+  setShouldRestoreHistory,
+  setSavedHistory,
+  getShouldRestoreHistory,
+  getSavedHistory,
+  clearHistoryRestore,
+} from "./historyRestore";
+
+describe("historyRestore module", () => {
+  beforeEach(() => {
+    clearHistoryRestore();
+  });
+
+  describe("initial state", () => {
+    it("shouldRestoreHistory is false by default", () => {
+      expect(getShouldRestoreHistory()).toBe(false);
+    });
+
+    it("savedHistory is null by default", () => {
+      expect(getSavedHistory()).toBeNull();
+    });
+  });
+
+  describe("setShouldRestoreHistory", () => {
+    it("sets shouldRestoreHistory to true", () => {
+      setShouldRestoreHistory(true);
+      expect(getShouldRestoreHistory()).toBe(true);
+    });
+
+    it("sets shouldRestoreHistory to false", () => {
+      setShouldRestoreHistory(true);
+      setShouldRestoreHistory(false);
+      expect(getShouldRestoreHistory()).toBe(false);
+    });
+  });
+
+  describe("setSavedHistory", () => {
+    it("sets the saved history string", () => {
+      setSavedHistory("some history content");
+      expect(getSavedHistory()).toBe("some history content");
+    });
+
+    it("sets the saved history to null", () => {
+      setSavedHistory("some history content");
+      setSavedHistory(null);
+      expect(getSavedHistory()).toBeNull();
+    });
+  });
+
+  describe("clearHistoryRestore", () => {
+    it("resets shouldRestoreHistory to false", () => {
+      setShouldRestoreHistory(true);
+      clearHistoryRestore();
+      expect(getShouldRestoreHistory()).toBe(false);
+    });
+
+    it("resets savedHistory to null", () => {
+      setSavedHistory("some content");
+      clearHistoryRestore();
+      expect(getSavedHistory()).toBeNull();
+    });
+
+    it("clears both values at once", () => {
+      setShouldRestoreHistory(true);
+      setSavedHistory("history");
+      clearHistoryRestore();
+      expect(getShouldRestoreHistory()).toBe(false);
+      expect(getSavedHistory()).toBeNull();
+    });
+  });
+});