rhg: support "status FILE" This change adds a new [file] argument to rhg status, parses them as patterns, canonicalizes the paths, and constructs a new PatternMatcher to intersect with the existing matcher being passed to the status implementation. We also make filepatterns a public module so we can access the pattern-parsing functionality we need from commands/status.rs.

--- a/rust/hg-core/src/lib.rs	Wed Aug 02 10:16:33 2023 -0400
+++ b/rust/hg-core/src/lib.rs	Wed Aug 02 10:46:47 2023 -0400
@@ -25,7 +25,7 @@
     DirstateEntry, DirstateParents, EntryState,
 };
 pub mod copy_tracing;
-mod filepatterns;
+pub mod filepatterns;
 pub mod matchers;
 pub mod repo;
 pub mod revlog;