Properly handle ignored files in the file finder (#31542)

Follow-up of https://github.com/zed-industries/zed/pull/31457

Add a button and also allows to use `search::ToggleIncludeIgnored`
action in the file finder to toggle whether to show gitignored files or
not.
By default, returns back to the gitignored treatment before the PR
above.


![image](https://github.com/user-attachments/assets/c3117488-9c51-4b34-b630-42098fe14b4d)


Release Notes:

- Improved file finder to include indexed gitignored files in its search
results

crates/file_finder/src/file_finder_settings.rs

@@ -8,6 +8,7 @@ pub struct FileFinderSettings {
     pub file_icons: bool,
     pub modal_max_width: Option<FileFinderWidth>,
     pub skip_focus_for_active_in_search: bool,
+    pub include_ignored: Option<bool>,
 }
 
 #[derive(Clone, Default, Serialize, Deserialize, JsonSchema, Debug)]
@@ -24,6 +25,20 @@ pub struct FileFinderSettingsContent {
     ///
     /// Default: true
     pub skip_focus_for_active_in_search: Option<bool>,
+    /// Determines whether to show the git status in the file finder
+    ///
+    /// Default: true
+    pub git_status: Option<bool>,
+    /// Whether to use gitignored files when searching.
+    /// Only the file Zed had indexed will be used, not necessary all the gitignored files.
+    ///
+    /// Can accept 3 values:
+    /// * `Some(true)`: Use all gitignored files
+    /// * `Some(false)`: Use only the files Zed had indexed
+    /// * `None`: Be smart and search for ignored when called from a gitignored worktree
+    ///
+    /// Default: None
+    pub include_ignored: Option<Option<bool>>,
 }
 
 impl Settings for FileFinderSettings {