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/worktree-names.test.ts

@@ -8,7 +8,7 @@ describe("generateWorktreeName", () => {
   let tempDir: string;
 
   beforeEach(() => {
-    tempDir = mkdtempSync(join(tmpdir(), "hai-wt-test-"));
+    tempDir = mkdtempSync(join(tmpdir(), "kb-wt-test-"));
   });
 
   afterEach(() => {