start splitting kfactory into subpackages

[sebastian-goeldi]

Summary by Sourcery

Enhancements:

• Begin modularizing the kfactory package by introducing dynamic imports for 'packing' and 'cells' submodules.

[sourcery-ai]

Reviewer's Guide by Sourcery

This PR implements lazy loading for subpackages in kfactory by modifying the package's init.py file. The implementation uses Python's getattr mechanism to dynamically import 'packing' and 'cells' submodules only when they are first accessed.

Class diagram for kfactory package restructuring

classDiagram
    class kfactory {
        +flexgrid_dbu
        +flexgrid
        +grid_dbu
        +grid
        +constant
        +config
        +dpolygon_from_array
        +kdb
        +lay
        +logger
        +placer
        +polygon_from_array
        +port
        +VInstance
        +VKCell
        +cell
        +__getattr__(name: str) ModuleType | None
    }
    note for kfactory "Lazy loading implemented for 'packing' and 'cells' submodules using __getattr__"

Loading

File-Level Changes

Change	Details	Files
Implement lazy loading for subpackages using getattr	Add getattr function to handle dynamic imports of 'packing' and 'cells' submodules Import required 'types' and 'importlib' modules Remove direct exports of 'cells' and 'packing' from all	src/kfactory/__init__.py

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[sourcery-ai]

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[sourcery-ai]

suggestion (code-quality): We've found these issues:

• Use set when checking membership of a collection of literals (collection-into-set)
• Use f-string instead of string concatenation (use-fstring-for-concatenation)

Suggested change

	if name in ["packing", "cells"]:
	return importlib.import_module("." + name, __name__)
	if name in {"packing", "cells"}:
	return importlib.import_module(f".{name}", __name__)

[github-actions]

Label error. Requires at least 1 of: breaking, bug, github_actions, documentation, dependencies, enhancement, feature, maintenance, security. Found: