Add meta descriptions for remaining guides (#10450)

## Summary

Closes https://github.com/astral-sh/uv/issues/10418.

docs/guides/integration/alternative-indexes.md

@@ -1,3 +1,10 @@
+---
+title: Using alternative package indexes
+description:
+  A guide to using alternative package indexes with uv, including Azure Artifacts, Google Artifact
+  Registry, AWS CodeArtifact, and more.
+---
+
 # Using alternative package indexes
 
 While uv uses the official Python Package Index (PyPI) by default, it also supports alternative

docs/guides/integration/dependency-bots.md

@@ -1,3 +1,8 @@
+---
+title: Using uv with dependency bots
+description: A guide to using uv with dependency bots like Renovate and Dependabot.
+---
+
 # Dependency bots
 
 It is considered best practice to regularly update dependencies, to avoid being exposed to

docs/guides/integration/github.md

@@ -1,3 +1,10 @@
+---
+title: Using uv in GitHub Actions
+description:
+  A guide to using uv in GitHub Actions, including installation, setting up Python, installing
+  dependencies, and more.
+---
+
 # Using uv in GitHub Actions
 
 ## Installation

docs/guides/integration/gitlab.md

@@ -1,3 +1,9 @@
+---
+title: Using uv in GitLab CI/CD
+description: A guide to using uv in GitLab CI/CD, including installation, setting up Python,
+  installing dependencies, and more.
+---
+
 # Using uv in GitLab CI/CD
 
 ## Using the uv image

docs/guides/integration/pytorch.md

@@ -1,3 +1,10 @@
+---
+title: Using uv with PyTorch
+description:
+  A guide to using uv with PyTorch, including installing PyTorch, configuring per-platform and
+  per-accelerator builds, and more.
+---
+
 # Using uv with PyTorch
 
 The [PyTorch](https://pytorch.org/) ecosystem is a popular choice for deep learning research and