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>

crates/extension/src/wasm_host/wit/since_v0_1_0.rs

@@ -356,8 +356,11 @@ impl ExtensionImports for WasmState {
                 cx.update(|cx| match category.as_str() {
                     "language" => {
                         let key = key.map(|k| LanguageName::new(&k));
-                        let settings =
-                            AllLanguageSettings::get(location, cx).language(key.as_ref());
+                        let settings = AllLanguageSettings::get(location, cx).language(
+                            location,
+                            key.as_ref(),
+                            cx,
+                        );
                         Ok(serde_json::to_string(&settings::LanguageSettings {
                             tab_size: settings.tab_size,
                         })?)

crates/extension/src/wasm_host/wit/since_v0_2_0.rs

@@ -402,8 +402,11 @@ impl ExtensionImports for WasmState {
                 cx.update(|cx| match category.as_str() {
                     "language" => {
                         let key = key.map(|k| LanguageName::new(&k));
-                        let settings =
-                            AllLanguageSettings::get(location, cx).language(key.as_ref());
+                        let settings = AllLanguageSettings::get(location, cx).language(
+                            location,
+                            key.as_ref(),
+                            cx,
+                        );
                         Ok(serde_json::to_string(&settings::LanguageSettings {
                             tab_size: settings.tab_size,
                         })?)