Optimize test suite with testing.Short() guards

- Add Short() guards to slow CLI tests (2-4s each)
- Add Short() guards to slow API/integration tests (3-11s)
- Add Short() guard to hanging daemon discovery test (29s timeout)
- Short test suite now runs in ~6s (down from 5+ minutes)

Run 'go test -short ./...' for fast iteration
Run 'go test ./...' for full coverage

Closes: bd-iov0

internal/importer/external_ref_test.go

@@ -11,6 +11,9 @@ import (
 )
 
 func TestImportWithExternalRef(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping slow import test in short mode")
+	}
 	ctx := context.Background()
 	tmpDir := t.TempDir()
 	dbPath := filepath.Join(tmpDir, "test.db")