Make `LSPAny` conform to `ExpressibleByStringLiteral` etc.

Constructing `LSPAny` objects could be simplified by making `LSPAny` conform to `ExpressibleByStringLiteral`, `ExpressibleByBoolLiteral`, `ExpressibleByDictionaryLiteral`, etc. Add these conformances in swift-tools-support and use them in sourcekit-lsp wherever possible. As this is a learning-oriented task, please don’t address this purely by using an AI tool, as described in https://github.com/swiftlang/project-operations/blob/main/contributing/ai-tools.md#learning-oriented-contributions.