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/character.test.ts

@@ -0,0 +1,124 @@
+import { describe, it, expect, beforeEach, vi, afterEach } from "vitest";
+import { get } from "svelte/store";
+import { characterState, characterInfo } from "./character";
+
+describe("characterState store", () => {
+  beforeEach(() => {
+    vi.useFakeTimers();
+    characterState.reset();
+  });
+
+  afterEach(() => {
+    vi.useRealTimers();
+  });
+
+  describe("initial state", () => {
+    it("starts in idle state", () => {
+      expect(get(characterState)).toBe("idle");
+    });
+  });
+
+  describe("setState", () => {
+    it("sets the character state", () => {
+      characterState.setState("thinking");
+      expect(get(characterState)).toBe("thinking");
+    });
+
+    it("can set any valid state", () => {
+      const states = [
+        "idle",
+        "thinking",
+        "typing",
+        "coding",
+        "searching",
+        "mcp",
+        "permission",
+        "success",
+        "error",
+      ] as const;
+      for (const state of states) {
+        characterState.setState(state);
+        expect(get(characterState)).toBe(state);
+      }
+    });
+
+    it("cancels any active temporary state timer", () => {
+      characterState.setTemporaryState("success", 5000);
+      characterState.setState("thinking");
+
+      // Advance past the temporary state duration — should stay as thinking
+      vi.advanceTimersByTime(6000);
+      expect(get(characterState)).toBe("thinking");
+    });
+  });
+
+  describe("setTemporaryState", () => {
+    it("sets the character state immediately", () => {
+      characterState.setTemporaryState("success", 2000);
+      expect(get(characterState)).toBe("success");
+    });
+
+    it("reverts to idle after the specified duration", () => {
+      characterState.setTemporaryState("success", 2000);
+      vi.advanceTimersByTime(2000);
+      expect(get(characterState)).toBe("idle");
+    });
+
+    it("uses 2000ms as the default duration", () => {
+      characterState.setTemporaryState("error");
+      vi.advanceTimersByTime(1999);
+      expect(get(characterState)).toBe("error");
+      vi.advanceTimersByTime(1);
+      expect(get(characterState)).toBe("idle");
+    });
+
+    it("cancels a previous temporary state timer when a new one is set", () => {
+      characterState.setTemporaryState("success", 5000);
+      characterState.setTemporaryState("error", 1000);
+
+      // First timer would have fired at 5000ms but was cancelled
+      vi.advanceTimersByTime(1000);
+      expect(get(characterState)).toBe("idle");
+    });
+  });
+
+  describe("reset", () => {
+    it("resets the state to idle", () => {
+      characterState.setState("thinking");
+      characterState.reset();
+      expect(get(characterState)).toBe("idle");
+    });
+
+    it("cancels any pending temporary state timer", () => {
+      characterState.setTemporaryState("success", 5000);
+      characterState.reset();
+
+      // Should now be idle and should NOT revert again after timer fires
+      expect(get(characterState)).toBe("idle");
+      vi.advanceTimersByTime(5000);
+      expect(get(characterState)).toBe("idle");
+    });
+  });
+});
+
+describe("characterInfo derived store", () => {
+  beforeEach(() => {
+    characterState.reset();
+  });
+
+  it("returns the info object for the current state", () => {
+    const info = get(characterInfo);
+    expect(info).toBeDefined();
+    expect(typeof info.label).toBe("string");
+  });
+
+  it("updates when the character state changes", () => {
+    characterState.setState("thinking");
+    const thinkingInfo = get(characterInfo);
+
+    characterState.setState("idle");
+    const idleInfo = get(characterInfo);
+
+    expect(thinkingInfo.label).not.toBe(idleInfo.label);
+  });
+});