refactor(HAI-116): rename kb to hai across all packages, CLI, and docs

- Rename npm packages from @kb/* to @hai/* and update all workspace references
- Rename CLI binary from kb to hai and config directory from .kb to .hai
- Update dashboard UI branding, titles, and references from kb to hai
- Update all test files, CI workflows, and documentation to reflect new naming
- Run comprehensive grep verification to ensure no stale kb references remain

packages/engine/src/scheduler.ts

@@ -1,4 +1,4 @@
-import { resolveDependencyOrder, type TaskStore, type Task } from "@hai/core";
+import { resolveDependencyOrder, type TaskStore, type Task } from "@kb/core";
 import type { AgentSemaphore } from "./concurrency.js";
 import { schedulerLog } from "./logger.js";