feat: implement hooks, plugins, session forks, and vim motions

Add 4 major features to codetyper-cli:

- Hooks System: Lifecycle hooks (PreToolUse, PostToolUse, SessionStart,
  SessionEnd, UserPromptSubmit, Stop) with exit code control flow
- Plugin System: Custom tools, commands, and hooks via plugin manifest
- Session Forking: Snapshots, rewind, fork, and switch between branches
- Vim Motions: Normal/Insert/Command/Visual modes with keyboard navigation

New files:
- src/types/{hooks,plugin,session-fork,vim}.ts
- src/constants/{hooks,plugin,session-fork,vim}.ts
- src/services/{hooks-service,plugin-loader,plugin-service,session-fork-service}.ts
- src/stores/vim-store.ts (vanilla)
- src/tui/hooks/{useVimMode,useVimStore,useTodoStore,useThemeStore}.ts
- src/tui/components/VimStatusLine.tsx

Modified:
- src/services/agent.ts (hook integration)
- src/tools/index.ts (plugin tool registration)
- src/stores/{todo-store,theme-store}.ts (converted to vanilla)
- TUI components (updated hook imports)

src/commands/components/execute/index.ts

@@ -23,6 +23,7 @@ import {
 } from "@utils/terminal";
 import { createCallbacks } from "@commands/chat-tui";
 import { agentLoader } from "@services/agent-loader";
+import { projectSetupService } from "@services/project-setup-service";
 
 interface ExecuteContext {
   state: ChatServiceState | null;
@@ -150,6 +151,9 @@ const execute = async (options: ChatTUIOptions): Promise<void> => {
     baseSystemPrompt: null,
   };
 
+  // Setup project on startup (add .codetyper to gitignore, create default agents)
+  await projectSetupService.setupProject(process.cwd());
+
   const { state, session } = await initializeChatService(options);
   ctx.state = state;
   // Store the original system prompt before any agent modifications