RFC: Change Default Output Style to XML

[yamadashy]

Proposal

Change the default output style from plain to xml in version 0.3.0.

Why?

• XML output provides better structure for AI processing
• I've been using XML as maintainer and found it more reliable
• Community feedback supports this change (see Discord discussion)

Impact

This is a breaking change that will require users who want plain text to explicitly specify:

repomix --style plain

or in config:

{
  "output": {
    "style": "plain"
  }
}

Version

• Release as version 0.3.0 to indicate breaking change
• Update documentation accordingly

Thoughts and feedback welcome!