Simpler field filter

[igitur]

Simpler Filter Syntax and Documentation Updates

Summary

• Added syntactic sugar for filter field definitions: field name filter filtername instead of field name * * * filtername
• Updated documentation to Texinfo 6.8 format
• Added documentation examples for the new filter syntax

Changes

1. Simpler Filter Syntax (e50643c)

• Modified src/parserc.c to support field name filter filtername syntax
• This is equivalent to the existing field name * * * filtername syntax
• Makes configuration files more readable and intuitive

2. Documentation Updates (a14bce7, 7b2c2f2)

• Updated HTML documentation generated by Texinfo 6.5 → 6.8
• Added documentation for the new filter syntax in all formats (HTML, Info, TeXinfo)
• Included practical examples showing usage:

  filter uppercase "tr '[:lower:]' '[:upper:]'"
  filter datefmt "date -f - '+%Y-%m-%d'"
  
  structure data {
      type separated ,
      record entry {
          field id
          field name filter uppercase
          field date filter datefmt
      }
  }

Benefits

• Improved readability: Clearer syntax for filter definitions
• Backward compatible: Old syntax still works
• Better documentation: Updated examples and modern formatting

[igitur]

hi @TimoSavi . After many years, I'm still a loyal user of your tool. I'm unsure whether this will break backwards compatibility, but I'm keen to hear your thoughts. Even if you don't like the syntactic sugar change, I'd love to update the documentation with better examples, which would assist an MCP like Context7 more.