Replace the vulcand/predicate dependency in the routing rules parser with a
direct go/parser/go/ast implementation covering the same grammar (matcher
calls, parentheses, &&/||/!). This removes the predicate -> gravitational/
trace -> logrus logging chain from x, since trace was only used to build
errors. Public API (NewParser, Parser, TreeBuilder, Parse, CheckRule,
ParseMatchers) is unchanged and the existing test suite passes as-is.
- Fix Host(".example.com") incorrectly matching bare "example.com" by
using HasSuffix(reqHost, host) instead of HasSuffix(reqHost, host[1:])
- Fix PathRegexp matcher error message saying "PathPrefix" instead of
"PathRegexp"
- Add doc comments to NewMatcher and Tree types
- Add 28 unit tests covering all matcher types, boolean operators,
edge cases, and parameter validation
ginuerzh