Miscellaneous improvements

• Disambiguate 'unexpected term type' panic messages (#84)
• Tidier IDENT syntax (#86)
• Cleanup temp file after make (#87)
• Reduce gc pressure (#89)

Clean up linter, module dependencies and CI

v0.23.0

make all in CI (#82)

New Scanner.Contains

Scanner.Contains: Checks if a scanner is part of another scanner

implement Scanner for Many and Branch

• feat: add MergeScanners function to merge multiple same-src Scanners

• feat: implement Scanner function for Many and Branch

Add source context to error message

• Add filename, line number and column number to error message.
• Fix a few bugs.

Various codegen fixes

v0.14.0

Add RefDiff

v0.13.0

Don't store a pointer

v0.12.2

fix failing test run

Generated walker API for wbnf users

v0.12.1

Generate a tree walker API to allow simple access to important nodes

v0.12.0

Fix data race in attemptRuleCompletion()