Initial import: the house-style lint rules as a crafter-build module

Moved out of Crafter.Build's lint-rules.h so a project.cpp pulls them in
with `#pragma crafter dependency` + `import Crafter.LintRules;` instead of
copying a header. The rule bodies are unchanged; format-concat now sits
with the other transforms (it rewrites, it was registered as a report),
and the helpers are module-internal. tests/HouseRules moved along with
the rules and links crafter-build from git, or the sibling checkout with
--local.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,2 @@
+bin/
+build/