feat: stuffy feature bundle (#159)

## Summary

This PR bundles a collection of new features and quality-of-life improvements identified during a Claude CLI 2.1.50 audit.

- **Tab status indicator** — Tab stays yellow until the greeting is responded to, then turns green. Fixed disconnect not resetting to grey. Closes #157
- **Auth status display** — New "Account" section in settings sidebar showing login status, email, org, API key source, and Hikari override indicator. Includes login/logout buttons. Closes #153
- **CLI version badge** — New "Supported" badge showing the highest audited CLI version, colour-coded green/amber/red based on installed vs supported version. Closes #154 (bump to 2.1.50)
- **Rate limit events** — `rate_limit_event` messages from the stream are now parsed and shown as amber `[rate-limit]` lines in the terminal instead of being silently dropped. Closes #155
- **"Prompt is too long" handling** — Detects this error in assistant messages and shows a ⚡ Compact Conversation button to send `/compact` directly. Closes #158
- **`last_assistant_message` in Agent Monitor** — Extracts the agent's final output from the `ToolResult` content block in the JSON stream and displays it as a snippet on completed agent cards. Closes #156
- **`--worktree` flag** — New "Worktree isolation" toggle in session settings passes `--worktree` to Claude Code. Hook events (`WorktreeCreate`/`WorktreeRemove`) are displayed as green `[worktree]` lines. Closes #152, Closes #150
- **ConfigChange hook events** — `[ConfigChange Hook]` stderr events are now displayed as cyan `[config]` lines instead of errors. Closes #151
- **`CLAUDE_CODE_DISABLE_1M_CONTEXT` toggle** — New "Disable 1M context" setting in session configuration injects this env var into the Claude process. Closes #154

## Test plan

- [ ] Tab status indicator: start a new session and verify the tab stays yellow until Claude responds to the greeting, then turns green
- [ ] Auth status: open settings and verify the Account section shows correct login info
- [ ] CLI version badge: verify the "Supported 2.1.50" badge shows green when CLI matches
- [ ] Rate limit events: unit tests cover parsing; amber `[rate-limit]` lines display correctly
- [ ] Compact button: unit tests cover detection; button renders correctly in terminal
- [ ] Agent Monitor: use the Task tool and verify completed agent cards show a message snippet
- [ ] Worktree: enable toggle, start session, verify `--worktree` flag appears in process args
- [ ] ConfigChange: hook events display as `[config]` lines rather than errors
- [ ] Disable 1M context: enable toggle, start session, verify `CLAUDE_CODE_DISABLE_1M_CONTEXT=1` in `/proc/<pid>/environ`

✨ This PR was created with help from Hikari~ 🌸

Reviewed-on: #159
Co-authored-by: Hikari <hikari@nhcarrigan.com>
Co-committed-by: Hikari <hikari@nhcarrigan.com>

src/lib/stores/agents.test.ts

@@ -177,6 +177,32 @@ describe("agents store", () => {
       const agents = get(getAgentsForConversation(conversationId));
       expect(agents[0].status).toBe("running"); // Status unchanged
     });
+
+    it("stores lastAssistantMessage when provided", () => {
+      const agent = createMockAgent({ status: "running" });
+      agentStore.addAgent(conversationId, agent);
+
+      agentStore.endAgent(
+        conversationId,
+        agent.toolUseId,
+        Date.now(),
+        false,
+        "Task completed successfully."
+      );
+
+      const agents = get(getAgentsForConversation(conversationId));
+      expect(agents[0].lastAssistantMessage).toBe("Task completed successfully.");
+    });
+
+    it("leaves lastAssistantMessage undefined when not provided", () => {
+      const agent = createMockAgent({ status: "running" });
+      agentStore.addAgent(conversationId, agent);
+
+      agentStore.endAgent(conversationId, agent.toolUseId, Date.now(), false);
+
+      const agents = get(getAgentsForConversation(conversationId));
+      expect(agents[0].lastAssistantMessage).toBeUndefined();
+    });
   });
 
   describe("markAllErrored", () => {

src/lib/stores/agents.ts

@@ -45,7 +45,13 @@ function createAgentStore() {
       });
     },
 
-    endAgent(conversationId: string, toolUseId: string, endedAt: number, isError: boolean) {
+    endAgent(
+      conversationId: string,
+      toolUseId: string,
+      endedAt: number,
+      isError: boolean,
+      lastAssistantMessage?: string
+    ) {
       agentsByConversation.update((state) => {
         const agents = state[conversationId];
         if (!agents) return state;
@@ -62,6 +68,7 @@ function createAgentStore() {
           endedAt,
           status: isError ? "errored" : "completed",
           durationMs,
+          lastAssistantMessage,
         };
 
         return {

src/lib/stores/config.test.ts

@@ -194,6 +194,8 @@ describe("config store", () => {
         budget_warning_threshold: 0.8,
         discord_rpc_enabled: true,
         show_thinking_blocks: true,
+        use_worktree: false,
+        disable_1m_context: false,
       };
 
       expect(config.model).toBe("claude-sonnet-4");
@@ -240,6 +242,8 @@ describe("config store", () => {
         budget_warning_threshold: 0.8,
         discord_rpc_enabled: true,
         show_thinking_blocks: true,
+        use_worktree: false,
+        disable_1m_context: false,
       };
 
       expect(config.model).toBeNull();
@@ -785,6 +789,8 @@ describe("config store", () => {
         budget_warning_threshold: 0.9,
         discord_rpc_enabled: false,
         show_thinking_blocks: true,
+        use_worktree: false,
+        disable_1m_context: false,
       };
 
       const mockInvokeImpl = vi.mocked(invoke);

src/lib/stores/config.ts

@@ -47,6 +47,10 @@ export interface HikariConfig {
   discord_rpc_enabled: boolean;
   // Thinking blocks settings
   show_thinking_blocks: boolean;
+  // Worktree isolation
+  use_worktree: boolean;
+  // Disable 1M context window
+  disable_1m_context: boolean;
 }
 
 const defaultConfig: HikariConfig = {
@@ -87,6 +91,8 @@ const defaultConfig: HikariConfig = {
   budget_warning_threshold: 0.8,
   discord_rpc_enabled: true,
   show_thinking_blocks: true,
+  use_worktree: false,
+  disable_1m_context: false,
 };
 
 function createConfigStore() {