docs: update installation section with multiple methods

- Add cargo-binstall as recommended method
- Add GitHub releases download option
- Update crates.io installation command
- Improve source build instructions

Author: asaaki

README.md

@@ -14,15 +14,34 @@ A tiny Rust-based CLI tool to generate unique IDs, primarily UUIDs. Built as a m
 
 ## Installation
 
+### With cargo-binstall (recommended)
+
+The fastest way to install pre-built binaries:
+
 ```bash
-cargo install --path .
+cargo binstall mkid
+```
+
+### From GitHub releases
+
+Download pre-built binaries directly from [GitHub releases](https://github.com/asaaki/mkid/releases).
+
+### From crates.io
+
+Build from source via crates.io:
+
+```bash
+cargo install mkid --locked
 ```
 
-Or build from source:
+### From source
+
+Build from the repository:
 
 ```bash
-cargo build --release
-# Binary available at target/release/mkid
+git clone https://github.com/asaaki/mkid
+cd mkid
+cargo install --path .
 ```
 
 ## Usage