[ENH] Enhance html repr

.pre-commit-config.yaml

@@ -70,7 +70,7 @@ repos:
         additional_dependencies: [black>=22.3.0]
       - id: nbqa-flake8
         args: [--nbqa-dont-skip-bad-cells, "--extend-ignore=E402,E203"]
-        additional_dependencies: [flake8==3.8.3]
+        additional_dependencies: [flake8==7.3.0]
 
   - repo: https://github.com/PyCQA/bandit
     rev: 1.9.4

pyproject.toml

@@ -144,6 +144,10 @@ exclude_dirs = ["*/tests/*", "*/testing/*"]
 zip-safe = true
 
 [tool.setuptools.package-data]
+skbase = [
+    "base/_pretty_printing/*.css",
+    "base/_pretty_printing/*.js",
+]
 sktime = [
     "*.csv",
     "*.csv.gz",

skbase/base/_meta.py

@@ -39,7 +39,7 @@ class has values that follow the named object specification. For example,
     # _steps_attr points to the attribute of self
     # which contains the heterogeneous set of estimators
     # this must be an iterable of (name: str, estimator) pairs for the default
-    _tags = {"named_object_parameters": "steps"}
+    _tags = {"named_object_parameters": "steps", "visual_block_kind": "serial"}
 
     def is_composite(self):
         """Check if the object is composite.
@@ -776,7 +776,7 @@ def _get_name(name, obj):
         names = [_get_name(name, est) for name, est in named_objects]
         name_details = [str(obj) for obj in objs]
         return _VisualBlock(
-            "serial",
+            self.get_tag("visual_block_kind", tag_value_default="serial"),
             objs,
             names=names,
             name_details=name_details,