Extract TOML support into an extension (#9940)

This PR extracts TOML support into an extension and removes the built-in
TOML support from Zed.

There's a small workaround necessary in order for us to set the file
permissions on the `taplo` binary so that it can be run. Eventually
we'll want to build this into the extension API, but for now we're just
hard-coding it on the host side.

Release Notes:

- Removed built-in support for TOML, in favor of making it available as
an extension. The TOML extension will be suggested for download when you
open a `.toml` or `Cargo.lock` file.

Cargo.toml

@@ -102,6 +102,7 @@ members = [
     "extensions/prisma",
     "extensions/purescript",
     "extensions/svelte",
+    "extensions/toml",
     "extensions/uiua",
     "extensions/zig",
 
@@ -324,7 +325,6 @@ tree-sitter-regex = "0.20.0"
 tree-sitter-ruby = "0.20.0"
 tree-sitter-rust = "0.20.3"
 tree-sitter-scheme = { git = "https://github.com/6cdh/tree-sitter-scheme", rev = "af0fd1fa452cb2562dc7b5c8a8c55551c39273b9" }
-tree-sitter-toml = { git = "https://github.com/tree-sitter/tree-sitter-toml", rev = "342d9be207c2dba869b9967124c679b5e6fd0ebe" }
 tree-sitter-typescript = { git = "https://github.com/tree-sitter/tree-sitter-typescript", rev = "5d20856f34315b068c41edaee2ac8a100081d259" }
 tree-sitter-vue = { git = "https://github.com/zed-industries/tree-sitter-vue", rev = "6608d9d60c386f19d80af7d8132322fa11199c42" }
 tree-sitter-yaml = { git = "https://github.com/zed-industries/tree-sitter-yaml", rev = "f545a41f57502e1b5ddf2a6668896c1b0620f930" }