Anvil v1.0.0 -- Arduino build tool with HAL and test scaffolding

Single-binary CLI that scaffolds testable Arduino projects, compiles,
uploads, and monitors serial output. Templates embed a hardware
abstraction layer, Google Mock infrastructure, and CMake-based host
tests so application logic can be verified without hardware.

Commands: new, doctor, setup, devices, build, upload, monitor
39 Rust tests (21 unit, 18 integration)
Cross-platform: Linux and Windows

.gitattributes

@@ -0,0 +1,23 @@
+# Auto-detect text files and normalize line endings
+* text=auto
+
+# Rust source
+*.rs text diff=rust
+*.toml text
+
+# Shell scripts must keep LF even on Windows
+*.sh text eol=lf
+
+# Batch scripts must keep CRLF
+*.bat text eol=crlf
+
+# C/C++ templates
+*.h text
+*.cpp text
+*.ino text
+
+# Documentation
+*.md text diff=markdown
+
+# Binary / generated -- do not diff
+Cargo.lock linguist-generated=true