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/README.md.tmpl

@@ -0,0 +1,74 @@
+# {{PROJECT_NAME}}
+
+Arduino project generated by Anvil v{{ANVIL_VERSION}}.
+
+## Quick Start
+
+```bash
+# Check your system
+anvil doctor
+
+# Find connected boards
+anvil devices
+
+# Compile only (no upload)
+anvil build --verify {{PROJECT_NAME}}
+
+# Compile and upload
+anvil build {{PROJECT_NAME}}
+
+# Compile, upload, and open serial monitor
+anvil build --monitor {{PROJECT_NAME}}
+
+# Run host-side unit tests (no board needed)
+cd test && ./run_tests.sh
+```
+
+## Project Structure
+
+```
+{{PROJECT_NAME}}/
+    {{PROJECT_NAME}}/
+        {{PROJECT_NAME}}.ino       Entry point (setup + loop)
+    lib/
+        hal/
+            hal.h                  Hardware abstraction interface
+            hal_arduino.h          Real hardware implementation
+        app/
+            {{PROJECT_NAME}}_app.h Application logic (testable)
+    test/
+        mocks/
+            mock_hal.h             Google Mock HAL
+            sim_hal.h              Stateful simulator HAL
+        test_unit.cpp              Unit tests
+        CMakeLists.txt             Test build system
+        run_tests.sh               Test runner (Linux/Mac)
+        run_tests.bat              Test runner (Windows)
+    .anvil.toml                    Project configuration
+```
+
+## Architecture
+
+All hardware access goes through the `Hal` interface. The app code
+(`lib/app/`) depends only on `Hal`, never on `Arduino.h` directly.
+This means the app can be compiled and tested on the host without
+any Arduino SDK.
+
+Two HAL implementations:
+- `ArduinoHal` -- passthroughs to real hardware (used in the .ino)
+- `MockHal` -- Google Mock for verifying exact call sequences in tests
+
+## Configuration
+
+Edit `.anvil.toml` to change board, baud rate, or build settings:
+
+```toml
+[build]
+fqbn = "arduino:avr:uno"
+warnings = "more"
+include_dirs = ["lib/hal", "lib/app"]
+extra_flags = ["-Werror"]
+
+[monitor]
+baud = 115200
+```