chore: clarify old stylelint warning

We get confused users thinking that Stylelint <14 won't work at all,
which isn't true. Though no support will be provided, it should work for
a while, hopefully enough time for plugins to get updated and users to
migrate. Updated the warning and the readme to clarify this subtlety.

README.md

@@ -68,7 +68,7 @@ _You can see or change the current document's language in the bottom-right corne
 
 > See also: [Stylelint 14 migration guide]
 
-vscode-stylelint 1.x expects to use Stylelint 14 at minimum. Usage with prior versions of Stylelint is not supported nor recommended. If you want to continue using this extension, upgrade your copy of Stylelint to version 14 or later.
+vscode-stylelint 1.x expects to use Stylelint 14 at minimum. Usage with prior versions of Stylelint is no longer supported. While older versions may continue to work for a while, you may encounter unexpected behaviour. You should upgrade your copy of Stylelint to version 14 or later for the best experience.
 
 The `syntax` and `configOverrides` options have been removed from Stylelint 14 and this extension. See the [following section](#%EF%B8%8F-only-css-and-postcss-are-validated-by-default) for information on how to use different syntaxes.
 

src/server/modules/__tests__/__snapshots__/old-stylelint-warning.ts.snap

@@ -11,6 +11,6 @@ Array [
 
 exports[`OldStylelintWarningModule without openDocument support, if Stylelint version is less than 14.x, should warn and provide link to migration guide 1`] = `
 Array [
-  "Stylelint version 13.0.0 is no longer supported — you may encounter unexpected behavior. Please upgrade to version 14.0.0 or newer. See the migration guide for more information.",
+  "Stylelint version 13.0.0 is no longer supported. While it may continue to work for a while, you may encounter unexpected behavior. Please upgrade to version 14.0.0 or newer. See the migration guide for more information.",
 ]
 `;

src/server/modules/old-stylelint-warning.ts

@@ -153,7 +153,7 @@ export class OldStylelintWarningModule implements LanguageServerModule {
 
 			this.#logger?.warn(`Found unsupported version of Stylelint: ${stylelintVersion}`);
 
-			const message = `Stylelint version ${stylelintVersion} is no longer supported — you may encounter unexpected behavior. Please upgrade to version 14.0.0 or newer. See the migration guide for more information.`;
+			const message = `Stylelint version ${stylelintVersion} is no longer supported. While it may continue to work for a while, you may encounter unexpected behavior. Please upgrade to version 14.0.0 or newer. See the migration guide for more information.`;
 
 			if (!this.#openMigrationGuide) {
 				this.#context.connection.window.showWarningMessage(message);