docs(notebooks): modernise icra2021.ipynb for the current API

[petercorke]

Notebook renovation, icra2021.ipynb (the code for the ICRA 2021 paper). It had 3 error cells against main; it now has none, and no warnings. No change to the toolbox.

What changed

• T.plot(label="2") is now T.plot(frame="2") (trplot takes frame, in the released spatialmath too).
• ETS.tz(), ETS.rz() and so on are now ET.tz(), ET.Rz(); ERobot is Robot.
• Box(..., base=...) is now Cuboid(..., pose=...) and collided is iscollided, which removes the FutureWarnings (both are in the released spatialgeometry 1.4.2).
• The standard generated first cell (docs(notebooks): a standard generated first cell, and a shorter bootstrap cell #850), crediting the paper's authors and noting the notebook was modernised on 2026-10-19 to address API drift.

Executed headless against main: 0 error cells and no warnings from the toolbox. Not tried in a browser. Written with AI assistance (Claude Code).

🤖 Generated with Claude Code

[codacy-production]

Up to standards ✅

🟢 Issues 0 issues

Results:
0 new issues

View in Codacy

_{NEW Get contextual insights on your PRs based on Codacy's metrics, along with PR and Jira context, without leaving GitHub. Enable AI reviewer
TIP This summary will be updated as you push new changes.}

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 0.00%. Comparing base (e778eb6) to head (838657c).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@          Coverage Diff          @@
##            main    #854   +/-   ##
=====================================
  Coverage   0.00%   0.00%           
=====================================
  Files        146     146           
  Lines      16866   16866           
=====================================
  Misses     16866   16866           

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.