feat: + write code only

[iorisa]

Features

• Added a process that directly allows Engineer to write code.

[codecov-commenter]

:warning: Please install the to ensure uploads and comments are reliably processed by Codecov.

Codecov Report

Attention: Patch coverage is 65.62500% with 11 lines in your changes missing coverage. Please review.

Project coverage is 62.31%. Comparing base (5446c7e) to head (5b34512).

Files	Patch %	Lines
metagpt/roles/engineer.py	20.00%	8 Missing :warning:
metagpt/actions/write_code.py	70.00%	3 Missing :warning:

:exclamation: Your organization needs to install the Codecov GitHub app to enable full functionality.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1421      +/-   ##
==========================================
- Coverage   62.34%   62.31%   -0.03%     
==========================================
  Files         283      283              
  Lines       17371    17388      +17     
==========================================
+ Hits        10830    10836       +6     
- Misses       6541     6552      +11     

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.

[geekan]

Afterwards, they will be merged together at once and will not be reviewed separately.