More efficient flat file list format and various UX improvements (#3)

This is a major upgrade with assorted things included.

- Navigation flows improved, search appears in URL history, cleared when navigating to another folder
- More efficient file list format for faster loads
- Efficient updates, never re-send full root another time (except at connection)
- Large number of watching and filelist updates (inotify issues remain)
- File size coloring
- Fixed ZIP generation random glitches (thread race condition)
- Code refactoring, cleanup, typing fixes
- More tests

Reviewed-on: #3

frontend/tsconfig.json

@@ -0,0 +1,14 @@
+{
+  "files": [],
+  "references": [
+    {
+      "path": "./tsconfig.node.json"
+    },
+    {
+      "path": "./tsconfig.app.json"
+    },
+    {
+      "path": "./tsconfig.vitest.json"
+    }
+  ]
+}