Use uv for venv creation in lc init (with python fallback)

[aboucaud]

Summary

• Replaces python -m venv + pip install with uv venv --python 3.12 + uv pip install in lc init for faster environment setup
• Gracefully falls back to the stdlib venv + pip path when uv is not available on the system
• Adds Rich status spinners to keep the user informed during both steps

Closes #102

Test plan

• test_init_venv_uses_uv_when_available — verifies uv venv --python 3.12 and uv pip install are called when uv is on PATH
• test_init_venv_falls_back_to_python_when_uv_missing — verifies python -m venv / pip install fallback when uv is absent

🤖 Generated with Claude Code

Signed-off-by: Alexandre Boucaud aboucaud@apc.in2p3.fr

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Status	Name	Latest Commit	Preview URL	Updated (UTC)
✅ Deployment successful! View logs	lightcone-cli	1d44859	Commit Preview URL Branch Preview URL	May 08 2026, 09:17 AM

[EiffL]

This looks good @aboucaud ! One question, does this modify the principle of having the venv in .venv? We curretrnyl have a hook that sources the .venv when claude starts. I think this doesn't change things, but just want to check

[aboucaud]

No it is transparent

[EiffL]

LGTM

[github-actions]

Developer Certificate of Origin

✅ All contributors have signed the DCO. This PR is ready to merge.

Status

• ✅ @aboucaud

[aboucaud]

I have read the Developer Certificate of Origin and I hereby sign the DCO for this PR

[github-actions]

✅ Eval Results

Metric	Value
Score	1.00
Build complete	✅
Cost	$0.78
Turns	29
Duration	435s
lightcone-cli	0.3.5.dev10+gc77826a57 (c77826a5)
Results	Download

Graders

✅ spec_valid (1.00)
✅ all_materialized (1.00)

Full output

09:16:24 lightcone.eval.build Building lightcone-cli wheel from /home/runner/work/lightcone-cli/lightcone-cli ...
09:16:29 lightcone.eval.build Built lightcone_cli-0.3.5.dev10+gc77826a57-py3-none-any.whl (commit c77826a5)
09:17:50 lightcone.eval.sandbox Created sandbox 1a4b6783-4a06-4ea3-8a19-b1e9b5f2c821 for trial build-snae-0
09:17:51 httpx HTTP Request: POST https://proxy.app.daytona.io/toolbox/1a4b6783-4a06-4ea3-8a19-b1e9b5f2c821/files/bulk-upload "HTTP/1.1 200 OK"
09:17:52 lightcone.eval.sandbox Installed wheels: ['lightcone_cli-0.3.5.dev10+gc77826a57-py3-none-any.whl']
09:17:53 httpx HTTP Request: POST https://proxy.app.daytona.io/toolbox/1a4b6783-4a06-4ea3-8a19-b1e9b5f2c821/files/bulk-upload "HTTP/1.1 200 OK"
09:17:53 httpx HTTP Request: POST https://proxy.app.daytona.io/toolbox/1a4b6783-4a06-4ea3-8a19-b1e9b5f2c821/files/bulk-upload "HTTP/1.1 200 OK"
09:17:53 httpx HTTP Request: POST https://proxy.app.daytona.io/toolbox/1a4b6783-4a06-4ea3-8a19-b1e9b5f2c821/files/bulk-upload "HTTP/1.1 200 OK"
09:17:54 httpx HTTP Request: POST https://proxy.app.daytona.io/toolbox/1a4b6783-4a06-4ea3-8a19-b1e9b5f2c821/files/bulk-upload "HTTP/1.1 200 OK"
09:25:10 lightcone.eval.sandbox Deleted sandbox for trial build-snae-0
  snae trial 0: score=1.00 complete

lightcone-cli: 0.3.5.dev10+gc77826a57 (HEAD c77826a5)
ASTRA: 0.2.7

  Eval Results: Scores  
┏━━━━━━┳━━━━━━━━━━━━━━━┓
┃ Task ┃     Score     ┃
┡━━━━━━╇━━━━━━━━━━━━━━━┩
│ snae │ 1.00 +/- 0.00 │
│      │ pass@k: 100%  │
└──────┴───────────────┘

   Eval Results: Cost &   
         Duration         
┏━━━━━━┳━━━━━━━━━━━━━━━━━┓
┃ Task ┃ Cost / Duration ┃
┡━━━━━━╇━━━━━━━━━━━━━━━━━┩
│ snae │      $0.78      │
│      │      434s       │
└──────┴─────────────────┘

Total: 1 trials, $0.78, 434s

Results saved to: eval-results/build-c77826a5/results.json