x/tools/gopls: support LSP 3.18

[adonovan]

At long last, LSP 3.18 is out:
https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification

gopls should use it.

Features to audit for potential uses:

• Added inline completions support.
• Added dynamic text document content support.
• Added refresh support for folding ranges.
• Support to format multiple ranges at once.
• Support for snippets in workspace edits.
• Relative Pattern support for document filters and notebook document filters.
• Support for code action kind documentation.
• Add support for activeParameter on SignatureHelp and SignatureInformation being null.
• Support tooltips for Command.
• Support for meta data information on workspace edits.
• Support for snippets in text document edits.
• Support for debug message kind.
• Client capability to enumerate properties that can be resolved for code lenses.
• Added support for completionList.applyKind to determine how values from completionList.itemDefaults and completion are combined.

[gopherbot]

Change https://go.dev/cl/795321 mentions this issue: gopls/internal/protocol: update to LSP 3.18

[gabyhelp]

Related Issues

• x/tools/gopls: initial support for pull-based diagnostics available in LSP 3.17 #53275 (closed)

_{(Emoji vote if this was helpful or unhelpful; more detailed feedback welcome in this discussion.)}

[gopherbot]

Change https://go.dev/cl/795442 mentions this issue: gopls/internal/protocol: use Debug log level

[adonovan]

The checked boxes above mean that I didn't think anything warranted immediate work. That's not to say we might not take advantage of of some of the new protocol features later.

[gopherbot]

Change https://go.dev/cl/796600 mentions this issue: gopls/internal/protocol/generate: remove manual rename overwritten