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/conversations.ts

@@ -43,6 +43,88 @@ export interface Conversation {
   draftText: string;
 }
 
+const TAB_NAMES = [
+  // Cosmic & celestial
+  "Starfall",
+  "Moonbeam",
+  "Nebula",
+  "Aurora",
+  "Stardust",
+  "Solstice",
+  "Comet",
+  "Eclipse",
+  "Zenith",
+  "Celestia",
+  "Nova",
+  "Quasar",
+  "Lyra",
+  "Andromeda",
+  "Twilight",
+  // Magical & fantastical
+  "Camelot",
+  "Reverie",
+  "Arcane",
+  "Spellbound",
+  "Mirage",
+  "Oracle",
+  "Seraphim",
+  "Ethereal",
+  "Labyrinth",
+  "Enchantment",
+  // Nature & cosy
+  "Sakura",
+  "Ember",
+  "Cascade",
+  "Zephyr",
+  "Serendipity",
+  "Solace",
+  "Blossom",
+  "Whisper",
+  "Dewdrop",
+  "Sunbeam",
+  "Willow",
+  "Clover",
+  "Honeybee",
+  "Buttercup",
+  "Dandelion",
+  // Japanese/anime-inspired
+  "Tsukimi",
+  "Hanami",
+  "Yozora",
+  "Hoshi",
+  "Koharu",
+  "Akari",
+  "Midori",
+  // Adventure & epic
+  "Odyssey",
+  "Wanderer",
+  "Horizon",
+  "Voyage",
+  "Pathfinder",
+  "Frontier",
+  // Whimsical & sweet
+  "Bubblegum",
+  "Marshmallow",
+  "Daydream",
+  "Whimsy",
+  "Jellybean",
+  "Sprinkle",
+  "Cupcake",
+  // Dreamy & poetic
+  "Revenant",
+  "Elysium",
+  "Halcyon",
+  "Ephemera",
+  "Serenade",
+  "Lullaby",
+  "Nocturne",
+  "Rhapsody",
+];
+
+function pickRandomTabName(): string {
+  return TAB_NAMES[Math.floor(Math.random() * TAB_NAMES.length)];
+}
+
 function createConversationsStore() {
   const conversations = writable<Map<string, Conversation>>(new Map());
   const activeConversationId = writable<string | null>(null);
@@ -63,7 +145,7 @@ function createConversationsStore() {
     const id = generateConversationId();
     return {
       id,
-      name: name || `Conversation ${conversationCounter}`,
+      name: name ?? pickRandomTabName(),
       terminalLines: [],
       sessionId: null,
       connectionStatus: "disconnected",
@@ -91,7 +173,7 @@ function createConversationsStore() {
   function ensureInitialized() {
     if (!initialized) {
       initialized = true;
-      const initialConversation = createNewConversation("Main");
+      const initialConversation = createNewConversation();
       conversations.update((convs) => {
         convs.set(initialConversation.id, initialConversation);
         return convs;