Fix config upgrade failures, save races, lock confirmation and release validation (#23)

* Coordinate config writes and gate releases on desktop validation

* Use toolkit rc.2 with painting and session lock fixes

* Ignore retired desktop widget settings in existing configs

shell/ferese-settings/Cargo.toml

@@ -10,7 +10,7 @@ ferese-theme-client = { path = "../../crates/ferese-theme-client" }
 ferese-theme = { path = "../../crates/ferese-theme" }
 ferese-config = { path = "../../crates/ferese-config" }
 libcosmic = { workspace = true, features = ["wgpu", "a11y", "xdg-portal"] }
-iced_accessibility = { git = "https://github.com/ferese-wm/libcosmic", tag = "ferese-v0.1.3-rc.1" }
+iced_accessibility.workspace = true
 ferese-ipc = { path = "../../crates/ferese-ipc" }
 serde_json.workspace = true
 tempfile.workspace = true