Update PHP language server docs (#44001)

Liffindra Angga Zaaldian and Piotr Osiewicz created

Reformat document structure like other language docs, improve
information flow, add missing requirements, and fix typos.

Release Notes:

- N/A

---------

Co-authored-by: Piotr Osiewicz <24362066+osiewicz@users.noreply.github.com>

Change summary

docs/src/languages/php.md | 114 ++++++++++++++++++++++++++++++++--------
1 file changed, 89 insertions(+), 25 deletions(-)

Detailed changes

docs/src/languages/php.md 🔗

@@ -2,34 +2,44 @@
 
 PHP support is available through the [PHP extension](https://github.com/zed-extensions/php).
 
-- Tree-sitter: https://github.com/tree-sitter/tree-sitter-php
-- Language Servers:
-  - [phpactor](https://github.com/phpactor/phpactor)
-  - [intelephense](https://github.com/bmewburn/vscode-intelephense/)
+- Tree-sitter: [tree-sitter/tree-sitter-php](https://github.com/tree-sitter/tree-sitter-php)
+- Language Server: [phpactor/phpactor](https://github.com/phpactor/phpactor)
+- Alternate Language Server: [bmewburn/vscode-intelephense](https://github.com/bmewburn/vscode-intelephense/)
 
-## Choosing a language server
+## Install PHP
 
-The PHP extension offers both `phpactor` and `intelephense` language server support.
+The PHP extension requires PHP to be installed and available in your `PATH`:
 
-`phpactor` is enabled by default.
+```sh
+# macOS via Homebrew
+brew install php
 
-### Phpactor
+# Debian/Ubuntu
+sudo apt-get install php-cli
 
-The Zed PHP Extension can install `phpactor` automatically but requires `php` to be installed and available in your path:
+# CentOS 8+/RHEL
+sudo dnf install php-cli
 
-```sh
-# brew install php            # macOS
-# sudo apt-get install php    # Debian/Ubuntu
-# yum install php             # CentOS/RHEL
-# pacman -S php               # Arch Linux
+# Arch Linux
+sudo pacman -S php
+
+# check PHP path
+## macOS and Linux
 which php
+
+## Windows
+where php
 ```
 
+## Choosing a language server
+
+The PHP extension uses [LSP language servers](https://microsoft.github.io/language-server-protocol) with Phpactor as the default. If you want to use other language servers that support Zed (e.g. Intelephense or PHP Tools), make sure to follow the documentation on how to implement it.
+
 ### Intelephense
 
-[Intelephense](https://intelephense.com/) is a [proprietary](https://github.com/bmewburn/vscode-intelephense/blob/master/LICENSE.txt#L29) language server for PHP operating under a freemium model. Certain features require purchase of a [premium license](https://intelephense.com/).
+[Intelephense](https://intelephense.com/) is a [proprietary](https://github.com/bmewburn/vscode-intelephense/blob/master/LICENSE.txt#L29) language server for PHP operating under a freemium model. Certain features require purchase of a [premium license](https://intelephense.com/buy).
 
-To switch to `intelephense`, add the following to your `settings.json`:
+To use Intelephense, add the following to your `settings.json`:
 
 ```json [settings]
 {
@@ -41,7 +51,9 @@ To switch to `intelephense`, add the following to your `settings.json`:
 }
 ```
 
-To use the premium features, you can place your [licence.txt file](https://intelephense.com/faq.html) at `~/intelephense/licence.txt` inside your home directory. Alternatively, you can pass the licence key or a path to a file containing the licence key as an initialization option for the `intelephense` language server. To do this, add the following to your `settings.json`:
+To use the premium features, you can place your license file inside your home directory at `~/intelephense/licence.txt` for macOS and Linux, or `%USERPROFILE%/intelephense/licence.txt` on Windows.
+
+Alternatively, you can pass the licence key or a path to a file containing the licence key as an initialization option. To do this, add the following to your `settings.json`:
 
 ```json [settings]
 {
@@ -55,15 +67,67 @@ To use the premium features, you can place your [licence.txt file](https://intel
 }
 ```
 
+### PHP Tools
+
+[PHP Tools](https://www.devsense.com/) is a proprietary language server that offers free and premium features. You need to [purchase a license](https://www.devsense.com/en/purchase) to activate the premium features.
+
+To use PHP Tools, add the following to your `settings.json`:
+
+```json [settings]
+{
+  "languages": {
+    "PHP": {
+      "language_servers": ["phptools", "!intelephense", "!phpactor", "..."]
+    }
+  }
+}
+```
+
+To use the premium features, you can add your license in `initialization_options` in your `settings.json`:
+
+```json [settings]
+{
+  "lsp": {
+    "phptools": {
+      "initialization_options": {
+        "0": "your_license_key"
+      }
+    }
+  }
+}
+```
+
+or, set environment variable `DEVSENSE_PHP_LS_LICENSE` on `.env` file in your project.
+
+```env
+DEVSENSE_PHP_LS_LICENSE="your_license_key"
+```
+
+Check out the documentation of [PHP Tools for Zed](https://docs.devsense.com/other/zed/) for more details.
+
+### Phpactor
+
+To use Phpactor instead of Intelephense or any other tools, add the following to your `settings.json`:
+
+```json [settings]
+{
+  "languages": {
+    "PHP": {
+      "language_servers": ["phpactor", "!intelephense", "!phptools", "..."]
+    }
+  }
+}
+```
+
 ## PHPDoc
 
 Zed supports syntax highlighting for PHPDoc comments.
 
 - Tree-sitter: [claytonrcarter/tree-sitter-phpdoc](https://github.com/claytonrcarter/tree-sitter-phpdoc)
 
-## Setting up Xdebug
+## Debugging
 
-Zed’s PHP extension provides a debug adapter for PHP and Xdebug. The adapter name is `Xdebug`. Here a couple ways you can use it:
+The PHP extension provides a debug adapter for PHP via Xdebug. There are several ways to use it:
 
 ```json
 [
@@ -83,10 +147,10 @@ Zed’s PHP extension provides a debug adapter for PHP and Xdebug. The adapter n
 ]
 ```
 
-In case you run into issues:
+These are common troubleshooting tips, in case you run into issues:
 
-- ensure that you have Xdebug installed for the version of PHP you’re running
-- ensure that Xdebug is configured to run in `debug` mode
-- ensure that Xdebug is actually starting a debugging session
-- check that the host and port matches between Xdebug and Zed
-- look at the diagnostics log by using the `xdebug_info()` function in the page you’re trying to debug
+- Ensure that you have Xdebug installed for the version of PHP you’re running.
+- Ensure that Xdebug is configured to run in `debug` mode.
+- Ensure that Xdebug is actually starting a debugging session.
+- Ensure that the host and port matches between Xdebug and Zed.
+- Look at the diagnostics log by using the `xdebug_info()` function in the page you’re trying to debug.