chore: add scripts to streamline source release

[xushiyan]

• add script to create src release
• add script to verify src release
• enable release branch CI

For #46

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 87.19%. Comparing base (cb9f4d8) to head (3f4289d).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #64 +/- ## ======================================= Coverage 87.19% 87.19% ======================================= Files 13 13 Lines 687 687 ======================================= Hits 599 599 Misses 88 88 ```

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