Add search (Ctrl+F, wildcards, match case/whole word) and sort, both off by default

Core.py

@@ -233,6 +233,24 @@ class AppConfig:
     # opposite of this default, so both are always one click away.
     OpenFilesInApp: bool = False
 
+    # Live filter for the file list, below the breadcrumbs/toolbar bar.
+    # ShowSearch is the master on/off; SearchAlwaysVisible picks between the
+    # bar always being there or only appearing on Ctrl+F (and dismissing on
+    # Escape). Match Case/Whole Word are session-only (Browser.MatchCase/
+    # MatchWholeWord), not persisted here — they're live search options, not
+    # a durable preference, same idea as a browser's find bar.
+    ShowSearch: bool = False
+    SearchAlwaysVisible: bool = False
+
+    # Sidebar sort control ("[Sort: Name] v" + a separate ascending/
+    # descending arrow button next to it — see Sidebar._BuildSortControl).
+    # Directories always sort before files regardless of field/direction,
+    # matching the existing list order; the field/direction only reorders
+    # within each of those two groups.
+    ShowSort: bool = False
+    SortField: str = "Name"  # "Name", "Size", "Modified", or "Type"
+    SortAscending: bool = True
+
     # Batch-rename pattern for multi-select rename, syntax modeled on
     # SaraSortd's own placeholder characters (see ~/Applications/SaraSortd's
     # GlobalConf.toml [Variables]): ~ = typed base name, ! = auto-incrementing