extensions: Yet another PR for debugger touchups (#32822)

We'll now clean up DAP locators for unloaded extensions and load schemas
proper

I can now load a custom Ruby extensions with all bells and whistles and
use it as my debugger.

Release Notes:

- N/A

docs/src/extensions/languages.md

@@ -27,6 +27,7 @@ line_comments = ["# "]
 - `tab_size` defines the indentation/tab size used for this language (default is `4`).
 - `hard_tabs` whether to indent with tabs (`true`) or spaces (`false`, the default).
 - `first_line_pattern` is a regular expression, that in addition to `path_suffixes` (above) or `file_types` in settings can be used to match files which should use this language. For example Zed uses this to identify Shell Scripts by matching the [shebangs lines](https://github.com/zed-industries/zed/blob/main/crates/languages/src/bash/config.toml) in the first line of a script.
+- `debuggers` is an array of strings that are used to identify debuggers in the language. When launching a debugger's `New Process Modal`, Zed will order available debuggers by the order of entries in this array.
 
 <!--
 TBD: Document `language_name/config.toml` keys