Revert "refactor: use libcosmic::dialog and make rfd optional"

This reverts commit a1c80efe69.

Cargo.lock

@@ -1073,6 +1073,7 @@ dependencies = [
  "log",
  "notify",
  "patch",
+ "rfd",
  "rust-embed",
  "serde",
  "syntect",
@@ -4388,6 +4389,12 @@ dependencies = [
  "windows-sys 0.52.0",
 ]
 
+[[package]]
+name = "pollster"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "22686f4785f02a4fcc856d3b3bb19bf6c8160d103f7a99cc258bddd0251dc7f2"
+
 [[package]]
 name = "powerfmt"
 version = "0.2.0"
@@ -4697,7 +4704,9 @@ dependencies = [
  "objc",
  "objc-foundation",
  "objc_id",
+ "pollster",
  "raw-window-handle 0.5.2",
+ "urlencoding",
  "wasm-bindgen",
  "wasm-bindgen-futures",
  "web-sys",
@@ -5818,6 +5827,12 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "urlencoding"
+version = "2.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "daf8dba3b7eb870caf1ddeed7bc9d2a049f3cfdfae7cb521b087cc33ae4c49da"
+
 [[package]]
 name = "usvg"
 version = "0.37.0"