Improve README

README.md

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 # mdtablefix
 
-This is a generated project using [Copier](https://copier.readthedocs.io/).
+`mdtablefix` reflows Markdown tables so that each column has a uniform width.
+It ignores fenced code blocks and respects escaped pipes (`\|`),
+making it safe for mixed content.
+
+## Installation
+
+```bash
+cargo install mdtablefix
+```
+
+or clone the repository and build from source:
+
+```bash
+cargo install --path .
+```
+
+## Command-line usage
+
+```bash
+mdtablefix [--in-place] [FILE...]
+```
+
+- With file paths provided, the corrected tables are printed to stdout.
+- Use `--in-place` to overwrite files.
+- If no files are supplied, input is read from stdin and results are written to stdout.
+
+### Example
+
+Before:
+
+```markdown
+| A|B |  C |
+|---|--|---|
+|1|22|333 |
+```
+
+After running `mdtablefix`:
+
+```markdown
+| A | B  | C   |
+| --- | --- | --- |
+| 1 | 22 | 333 |
+```
+
+## Library usage
+
+The crate exposes helper functions so you can integrate the table reflow logic
+in your own project.
+
+```rust
+use mdtablefix::{process_stream, rewrite};
+use std::path::Path;
+
+fn main() -> std::io::Result<()> {
+    let lines = vec!["|A|B|".to_string(), "|1|2|".to_string()];
+    let fixed = process_stream(&lines);
+    println!("{}", fixed.join("\n"));
+    rewrite(Path::new("table.md"))?;
+    Ok(())
+}
+```
+
+- `process_stream(&[String]) -> Vec<String>` rewrites tables in memory.
+- `rewrite(&Path) -> std::io::Result<()>` updates a Markdown file on disk.
+
+## Testing
+
+See `docs/rust-testing-with-rstest-fixtures.md` for notes on how the test suite
+is organised using the [`rstest`](https://crates.io/crates/rstest) crate.
+
+## License
+
+This project is licensed under the ISC license.
+See the [LICENSE](LICENSE) file for details.
 
-A tool to reflow Markdown tables while preserving other document content.
-It also converts simple HTML `<table>` elements to Markdown before reflowing.