release: align demo 0.2.0 with base-cli 0.5.1

[codeforester]

Refs #55

Summary

• refresh the locked framework to published base-cli 0.5.1
• update current Base-CLI documentation links and release wording
• retain the supported compatibility floor of base-cli>=0.5.0,<0.6

Validation

• 70 pytest tests passed
• uv lock --check passed
• wheel and sdist build passed
• Twine metadata checks passed
• git diff --check passed

The existing v0.2.0 draft tag points to the prior preparation commit. After this PR merges, that unpublished draft tag/release will be recreated on the reviewed merge commit before the draft asset workflow runs.