Convert CLI reference section headers and titles to sentence case (#1381)

Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>
Co-authored-by: Devin Logan <[email protected]>

Author: devin-ai-integration[bot]

fern/products/cli-api-reference/cli-api-reference.yml

@@ -1,5 +1,5 @@
 navigation:
-  - section: CLI Reference
+  - section: CLI reference
     contents:
       - page: Get started with Fern CLI
         path: ./pages/cli-get-started.mdx

fern/products/cli-api-reference/pages/cli-get-started.mdx

@@ -4,7 +4,7 @@ subtitle: Manage and configure your Fern projects, all from the command line.
 description: 'Overview of the Fern CLI including usage, installation, and CI/CD environments'
 ---
 
-## Installing Fern CLI
+## Install Fern CLI
 
 Run the following command to download and install Fern CLI from the [npm](https://www.npmjs.com/) registry. 
 
@@ -13,7 +13,7 @@ npm install -g fern-api # install Fern CLI
 fern -v # ensure Fern was successfully installed
 ```
 
-<Accordion title="Installing Fern CLI locally" toc={true}>
+<Accordion title="Install Fern CLI locally" toc={true}>
 
 If you're experiencing network delays with the global installation, working in an environment with limited internet connectivity, or prefer to manage Fern as a project dependency, you can install the CLI locally:
 

fern/products/cli-api-reference/pages/commands.mdx

@@ -15,14 +15,14 @@ hideOnThisPage: true
 | [`fern export`](#fern-export) | Export an OpenAPI spec for your API |
 | [`fern api update`](#fern-api-update) | Manually update your OpenAPI spec |
 
-## Documentation Commands
+## Documentation commands
 
 | Command | Description |
 |---------|-------------|
 | [`fern docs dev`](#fern-docs-dev) | Run local documentation preview server |
 | [`fern generate --docs`](#fern-generate---docs) | Build & publish documentation updates |
 
-## SDK Generation Commands  
+## SDK generation commands  
 
 | Command | Description |
 |---------|-------------|
@@ -31,7 +31,7 @@ hideOnThisPage: true
 | [`fern write-overrides`](#fern-write-overrides) | Create OpenAPI customizations |
 | [`fern generator upgrade`](#fern-generator-upgrade) | Update SDK generators to latest versions |
 
-## Detailed Command Documentation
+## Detailed command documentation
 
 <AccordionGroup>
   <Accordion title="fern init">

fern/products/cli-api-reference/pages/global-options.mdx

@@ -4,7 +4,7 @@ description: 'Global options for the Fern CLI'
 subtitle: 'Explore Fern CLI global options.'
 ---
 
-## Quick Reference
+## Quick reference
 
 | Option | Description | Example |
 |--------|-------------|---------|
@@ -98,4 +98,4 @@ fern generate --api payments-api --group python-sdk --version 1.2.3
 
 # Generate TypeScript SDK for the auth API with version 0.1.0
 fern generate --api auth --group ts-sdk --version 0.1.0
-```
+```