chore: release 1.4.0

[github-actions]

🤖 I have created a release beep boop

1.4.0 (2026-07-03)

Features

• change collision backend from PyBullet to Coal (f99c154)
• refactor URDF loading, add Jaco model, fix collision and deepcopy (d8f9289)

Bug Fixes

• bdsim blocks and tests (43e89cf)
• deps: add coal/trimesh to dev extras (#528) (3bb5847)
• docstrings in robot models (912cc4b)
• models: add missing URDFRobot.py and Jaco.py (839ab74)
• models: fall back to robot_descriptions' new naming, hide wrapped dependency on failure (#529) (d8441a3)
• rtb-data: add missing rtb-data package config and data files (aaff234)
• URDF parser (39f14a0)
• xacro: use quoteattr for attribute serialization (Python 3.14) (34bb4e2), closes #511

Documentation

• add desiderata (design principles) (104671e)
• README update (e691441)
• tech-debt: note rtb-data auto-publish idea (c3cfcb2)

Build System

• deps: bump actions/checkout from 6 to 7 (#522) (65feed3)
• deps: bump actions/upload-pages-artifact from 3 to 5 (#521) (874e4a5)
• deps: bump amannn/action-semantic-pull-request from 5 to 6 (#525) (9acab8b)
• deps: bump googleapis/release-please-action from 4 to 5 (#524) (a5e59ed)
• deps: bump softprops/action-gh-release from 2 to 3 (#523) (1e6183f)
• exclude rtb-data subdir from sdist (e45363d)
• remove rules for pushing to PyPI, now done by GH actions. (569fedd)

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