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

templates/basic/_dot_anvil.toml.tmpl

@@ -0,0 +1,12 @@
+[project]
+name = "{{PROJECT_NAME}}"
+anvil_version = "{{ANVIL_VERSION}}"
+
+[build]
+fqbn = "arduino:avr:uno"
+warnings = "more"
+include_dirs = ["lib/hal", "lib/app"]
+extra_flags = ["-Werror"]
+
+[monitor]
+baud = 115200