Feat/glob filtering

[sidisinsane]

Added

• Glob filtering for generate. ScanDir now accepts include and
  exclude pattern slices and matches them against each file's path relative to
  the scanned directory using filepath.Match.

  • include — whitelist of patterns. Only matching .sh files are processed.
    Empty means include all.
  • exclude — blacklist of patterns. Matching files are skipped. Takes
    precedence over include.
  • Invalid patterns are silently ignored.

• Documentation for filter fields in hashfm-agent/README.md (config example

  • field reference table).

Fixed

• TSV generator line-break sanitisation. Descriptions containing embedded
  newlines (from folded/literal YAML scalars) are now collapsed into single
  spaces, restoring the one-entry-per-line TSV guarantee.