Support .editorconfig (#19455)

Closes https://github.com/zed-industries/zed/issues/8534
Supersedes https://github.com/zed-industries/zed/pull/16349

Potential concerns:
* we do not follow up to the `/` when looking for `.editorconfig`, only
up to the worktree root.
Seems fine for most of the cases, and the rest should be solved
generically later, as the same issue exists for settings.json
* `fn language` in `AllLanguageSettings` is very hot, called very
frequently during rendering. We accumulate and parse all `.editorconfig`
file contents beforehand, but have to go over globs and match these
against the path given + merge the properties still.
This does not seem to be very bad, but needs more testing and
potentially some extra caching.


Release Notes:

- Added .editorconfig support

---------

Co-authored-by: Ulysse Buonomo <buonomo.ulysse@gmail.com>

Cargo.lock

@@ -3649,6 +3649,12 @@ version = "1.0.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0d6ef0072f8a535281e4876be788938b528e9a1d43900b82c2569af7da799125"
 
+[[package]]
+name = "ec4rs"
+version = "1.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "acf65d056c7da9c971c2847ce250fd1f0f9659d5718845c3ec0ad95f5668352c"
+
 [[package]]
 name = "ecdsa"
 version = "0.14.8"
@@ -6210,6 +6216,7 @@ dependencies = [
  "clock",
  "collections",
  "ctor",
+ "ec4rs",
  "env_logger",
  "futures 0.3.30",
  "fuzzy",
@@ -10302,6 +10309,7 @@ version = "0.1.0"
 dependencies = [
  "anyhow",
  "collections",
+ "ec4rs",
  "fs",
  "futures 0.3.30",
  "gpui",