feat(KB-141): fix workspace type resolution and add clean-checkout typecheck tests

- Remove dist-dependent workspace type resolution from all tsconfig files

- Add clean-checkout typecheck regression test to CI suite

- Update package.json type definitions for core, engine, dashboard, and cli packages

- Update README with typecheck testing documentation

- Clean up unused test files and component dependencies

packages/dashboard/app/components/TerminalModal.tsx

@@ -3,6 +3,7 @@ import { X, Trash2, Terminal as TerminalIcon, RefreshCw } from "lucide-react";
 import { useTerminal } from "../hooks/useTerminal";
 import { createTerminalSession, killPtyTerminalSession } from "../api";
 import type { Terminal as XTerm, ITerminalAddon } from "@xterm/xterm";
+import type { FitAddon } from "@xterm/addon-fit";
 
 import "@xterm/xterm/css/xterm.css";