teeny gramatical error in docs (astral-sh#12908)

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## Summary

<!-- What's the purpose of the change? What does it do, and why? -->

Incorrect use of the indefinite article- 'an project' instead of 'a
project'

## Test Plan

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Was not tested due to it being a small change to docs wording without
change in formatting.

Author: dasAtRagedy

docs/guides/integration/fastapi.md

@@ -42,7 +42,7 @@ To use uv with this application, inside the `project` directory run:
 $ uv init --app
 ```
 
-This creates an [project with an application layout](../../concepts/projects/init.md#applications)
+This creates a [project with an application layout](../../concepts/projects/init.md#applications)
 and a `pyproject.toml` file.
 
 Then, add a dependency on FastAPI:

docs/guides/scripts.md

@@ -351,6 +351,24 @@ PS> uv run --with PyQt5 example_pyqt.pyw
 
 ![Run Result](../assets/uv_gui_script_hello_world_pyqt.png){: style="height:50px;width:150px"}
 
+## Setting a shebang
+
+You can use the following shebang (`#!`) line at the top of your script to have your system pick `uv` for running it:
+
+```python title="example.py"
+#!/usr/bin/env -S uv run --script
+# /// script
+# dependencies = []
+# ///
+```
+
+You can then make the script executable and launch it without explicitly calling `uv`:
+
+```bash
+chmod +x example.py
+./example.py
+```
+
 ## Next steps
 
 To learn more about `uv run`, see the [command reference](../reference/cli.md#uv-run).