Fix small issues

[MaxStalker]

Changes

• New language client was created after switch to another editor. Fixed by storing and reusing language clients
• Fix language server error, when starting with empty project
• Decode browser tab and description from project title (special characters were in Helmet title)

Tests

• - Manually Tested. All working properly 👌

There are nor unit nor integration tests in Playground - those would require an issue of their own first 🤷

[vercel]

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