Overhaul hooklist API to fully catch all add/delete events

[kenblu24]

• Moved HookList to utils.py
• World.population and World.objects are now properties
• Fixed World.quad not being defined at init time
• BinaryFOVSensor will skip update if world.quad is None
• HookLists now properly calls add/delete callbacks on all list modification operations, i.e. extend, insert, setitem, etc.
  • Previously, HookList only notified callbacks on .append
  • HookList.__setitem__ (i.e. population[:] = iterable) calls del_callback on the items being replaced and add_callback on the new items
  • each func in HookList._add_callbacks is called for:
    • HookList.__init__ (if you somehow manage to create a new one with callbacks on it)
    • HookList.append
    • HookList.extend
    • HookList.insert
    • HookList.__iadd__
    • HookList.__imul__
    • HookList.__setitem__
  • each func in HookList._del_callbacks is called for:
    • HookList.pop
    • HookList.remove
    • HookList.__setitem__

[Copilot]

Pull Request Overview

This PR overhauls the HookList API to comprehensively capture all list modification events, moving the implementation to a dedicated utils module and fixing several initialization and callback issues.

Key changes:

• Moved HookList implementation from World.py to utils/collections.py with enhanced callback support
• Converted World.population and World.objects to properties with proper HookList backing
• Fixed World.quad initialization and BinaryFOVSensor handling of None quad values

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/swarmsim/world/World.py	Moved HookList to utils, converted population/objects to properties with private backing fields
src/swarmsim/world/RectangularWorld.py	Updated method names to snake_case and fixed quad initialization
src/swarmsim/util/collections.py	Added comprehensive HookList implementation with full callback support
src/swarmsim/sensors/BinaryFOVSensor.py	Added null check for world.quad and updated property reference
demo/population_hook_test.py	Updated to use new HookList callback registration methods

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