Enable CPU CI: upstream CI enabling with github workflow

[DiweiSun]

Motivation

Modifications

Checklist

• Format your code according to the Code Formatting with Pre-Commit.
• Add unit tests as outlined in the Running Unit Tests.
• Update documentation / docstrings / example tutorials as needed, according to Writing Documentation.
• Provide throughput / latency benchmark results and accuracy evaluation results as needed, according to Benchmark and Profiling and Accuracy Results.
• For reviewers: If you haven't made any contributions to this PR and are only assisting with merging the main branch, please remove yourself as a co-author when merging the PR.
• Please feel free to join our Slack channel at https://slack.sglang.ai to discuss your PR.

[DiweiSun]

Test Results for PR #3

test/srt/test_custom_allreduce.py::TestCustomAllReduce::test_eager_allreduce PASSED [ 50%]
test/srt/test_custom_allreduce.py::TestCustomAllReduce::test_graph_allreduce PASSED [100%]

============================== 2 passed in 3.80s ===============================
============================================
Final test result: success
============================================
All tests completed successfully
ci_sglang_cpu

Full log available in Jenkins build: https://cje-fm-owrp-prod03.devtools.intel.com/stag-aia-fwkval/job/sglang_postci_regular/71/

[DiweiSun]

## Test Results for PR #3 ✅
**Build Status:** SUCCESS

### Benchmark Results
| Metric | Value |
|--------|-------|
| Total Latency | N/A s |
| Total Throughput | N/A tokens/s |
| Median Latency | N/A s |
| Median Throughput | N/A tokens/s |

### Unit Test Results
**Passed:** 6  
**Failed:** 2

```text
+ echo '| Median Latency | 0.03975 s |'

• echo '| Median Throughput | 50.31 tokens/s |'
• echo ''
• echo '## Unit Test Results'
• echo ''
• docker exec -w /root/sglang ci_sglang_cpu pytest -v test/srt/test_custom_allreduce.py
• tee /home/pytorch/workspace/sglang_postci_regular/sglang/pytest.log
  ============================= test session starts ==============================
  platform linux -- Python 3.12.9, pytest-8.3.5, pluggy-1.5.0 -- /root/miniforge3/bin/python3.12
  cachedir: .pytest_cache
  rootdir: /root/sglang
  plugins: anyio-4.9.0
  collecting ... collected 2 items

test/srt/test_custom_allreduce.py::TestCustomAllReduce::test_eager_allreduce PASSED [ 50%]
test/srt/test_custom_allreduce.py::TestCustomAllReduce::test_graph_allreduce PASSED [100%]

============================== 2 passed in 3.74s ===============================
++ grep -c PASSED /home/pytorch/workspace/sglang_postci_regular/sglang/pytest.log

• PASSED_TESTS=2
  ++ grep -c FAILED /home/pytorch/workspace/sglang_postci_regular/sglang/pytest.log
  ++ true
• FAILED_TESTS=0
• echo '```text'
• cat /home/pytorch/workspace/sglang_postci_regular/sglang/pytest.log
• echo '```'
• echo ''
• echo 'Summary: 2 passed, 0 failed'
• echo ''
• echo ---
• '[' success = success ']'
• echo '✅ All tests completed successfully'
• echo ============================================
  ============================================
• cat /home/pytorch/workspace/sglang_postci_regular/sglang/test_results.md

Test Results

Docker Build Results

✅ Docker build succeeded

Benchmark Results

Metric	Value
Total Latency	1.316 s
Total Throughput	97.28 tokens/s
Median Latency	0.03975 s
Median Throughput	50.31 tokens/s

Unit Test Results

============================= test session starts ==============================
platform linux -- Python 3.12.9, pytest-8.3.5, pluggy-1.5.0 -- /root/miniforge3/bin/python3.12
cachedir: .pytest_cache
rootdir: /root/sglang
plugins: anyio-4.9.0
coll
    ```
    
    [View Full Build Log](https://cje-fm-owrp-prod03.devtools.intel.com/stag-aia-fwkval/job/sglang_postci_regular/101/)
    

[DiweiSun]

Test Results

Docker Build Results

✅ Docker build succeeded

Benchmark Results

Metric	Value
Total Latency	1.373 s
Total Throughput	93.22 tokens/s
Median Latency	0.04128 s
Median Throughput	48.45 tokens/s

Unit Test Results

============================= test session starts ==============================
platform linux -- Python 3.12.9, pytest-8.3.5, pluggy-1.5.0 -- /root/miniforge3/bin/python3.12
cachedir: .pytest_cache
rootdir: /root/sglang
plugins: anyio-4.9.0
collecting ... collected 2 items

test/srt/test_custom_allreduce.py::TestCustomAllReduce::test_eager_allreduce PASSED [ 50%]
test/srt/test_custom_allreduce.py::TestCustomAllReduce::test_graph_allreduce PASSED [100%]

============================== 2 passed in 3.83s ===============================

Summary: 2 passed, 0 failed

---

✅ All tests completed successfully