Add comprehensive documentation

- Update README.md with installation, quick start, and features
- Add api_overview.md for LLM-parseable API reference
- Expand Documenter.jl docs with examples and API pages
- Fix docs/Project.toml to use local package path

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: kalidke

README.md

@@ -1,6 +1,55 @@
-# NIDAQmx
+# NIDAQmx.jl
 
 [![Stable](https://img.shields.io/badge/docs-stable-blue.svg)](https://LidkeLab.github.io/NIDAQmx.jl/stable/)
 [![Dev](https://img.shields.io/badge/docs-dev-blue.svg)](https://LidkeLab.github.io/NIDAQmx.jl/dev/)
 [![Build Status](https://github.com/LidkeLab/NIDAQmx.jl/actions/workflows/CI.yml/badge.svg?branch=main)](https://github.com/LidkeLab/NIDAQmx.jl/actions/workflows/CI.yml?query=branch%3Amain)
 [![Coverage](https://codecov.io/gh/LidkeLab/NIDAQmx.jl/branch/main/graph/badge.svg)](https://codecov.io/gh/LidkeLab/NIDAQmx.jl)
+
+A Julia wrapper for National Instruments NI-DAQmx driver, providing type-safe access to NI data acquisition hardware.
+
+## Installation
+
+```julia
+using Pkg
+Pkg.add(url="https://github.com/LidkeLab/NIDAQmx.jl")
+```
+
+Requires NI-DAQmx driver to be installed on your system.
+
+## Quick Start
+
+```julia
+using NIDAQmx
+
+# List available devices
+devs = devices()
+
+# Analog input: read 100 samples at 1 kHz
+task = AITask("Dev1/ai0")
+configure_timing!(task; rate=1000.0, samples_per_channel=100)
+start!(task)
+data = read(task)
+stop!(task)
+
+# Analog output: write a sine wave
+task = AOTask("Dev1/ao0")
+write(task, sin.(2π .* (0:99) ./ 100))
+```
+
+## Features
+
+- Parametric task types (`AITask`, `AOTask`, `DITask`, `DOTask`, `CITask`, `COTask`) for type-safe dispatch
+- Julia enums for terminal configuration, edge detection, sample modes
+- Automatic task handle cleanup via finalizers
+- Support for analog, digital, and counter I/O
+- Timing configuration: sample clock, implicit, change detection
+- Trigger support: digital edge, analog edge, analog window
+
+## Documentation
+
+- [API Reference](api_overview.md) - Complete function and type documentation
+- [Full Documentation](https://LidkeLab.github.io/NIDAQmx.jl/dev/) - Guides and examples
+
+## License
+
+MIT License - see [LICENSE](LICENSE) file.