Refactor project configuration to use .json format

- Replaced the legacy .json5 project file with a new .json format for `plugin.project.json`.
- Updated `build.rs` to prioritize the new .json format while maintaining backward compatibility with .json5.
- Made adjustments to the Confirming.lua file to enhance UI consistency.
- Improved metadata handling in snapshot middleware to support both modern and legacy file extensions.

plugin/src/App/StatusPages/Confirming.lua

@@ -327,18 +327,18 @@ function ConfirmingPage:render()
 					self:setState({ showingAcceptConfirm = false })
 				end,
 			}, {
-				Content = e("Frame", {
-					Size = UDim2.fromScale(1, 1),
-					BackgroundColor3 = theme.Background2,
-					BorderSizePixel = 0,
-				}, {
-					Message = e("TextLabel", {
-						Text = string.format(
-							"%d item%s not been reviewed.\n\nAccept selected changes and skip the rest?",
-							self.state.unselectedCount,
-							self.state.unselectedCount == 1 and " has" or "s have"
-						),
-						FontFace = theme.Font.Regular,
+			Content = e("Frame", {
+				Size = UDim2.fromScale(1, 1),
+				BackgroundColor3 = theme.BackgroundColor,
+				BorderSizePixel = 0,
+			}, {
+				Message = e("TextLabel", {
+					Text = string.format(
+						"%d item%s not been reviewed.\n\nAccept selected changes and skip the rest?",
+						self.state.unselectedCount,
+						self.state.unselectedCount == 1 and " has" or "s have"
+					),
+					FontFace = theme.Font.Main,
 						TextSize = theme.TextSize.Body,
 						TextColor3 = theme.TextColor,
 						TextWrapped = true,