fix(demo): copy hatch_build.py into the image build context

[plind-junior]

the demo image build broke when pyproject.toml gained the hatch_build.py build hook (console bundling): pip install of /src fails before dependency resolution because the hook file was never copied into the build context. one-line copy fixes it; verified by rebuilding the image locally.

Summary by CodeRabbit

• Bug Fixes
  • Fixed demo container builds by ensuring required packaging configuration is available during dependency installation.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: 3bb2893f-ab56-4fa8-b9ba-b4b1ecbce675

📥 Commits

Reviewing files that changed from the base of the PR and between 5363642 and 15ac67a.

📒 Files selected for processing (1)

• demo/Dockerfile

---

📝 Walkthrough

Walkthrough

The runtime Docker stage now copies hatch_build.py into /src/ with pyproject.toml and README.md, allowing the sdist build backend to resolve its build hook.

Changes

Docker build preparation

Layer / File(s)	Summary
Include Hatch build hook demo/Dockerfile	The runtime-stage source copy includes hatch_build.py and explains why it is required before dependency resolution.

Estimated code review effort: 1 (Trivial) | ~2 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly describes the main fix: adding hatch_build.py to the demo image build context.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/demo-hatch-build

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}