feat(findNvim): version parsing robustness

Problem:
Version parsing makes some assumptions about the `nvim -v` output that
could be more robust. For example,
- "NVIM" may change to "Nvim": neovim/neovim@98ba65b
- "v" is not guaranteed to precede the version

Solution:
- match case-insensitive "NVIM"
- match "v?" instead of "v"
- Note: `--api-info` is not used because it is a big payload (thus
  requires streamed decoding, thus more complex code).

Author: justinmk

CHANGELOG.md

@@ -2,7 +2,7 @@
 
 ## [5.4.0](https://github.com/neovim/node-client/compare/v5.3.0...v5.4.0)
 
-- TODO
+- feat(findNvim): version parsing robustness
 
 ## [5.3.0](https://github.com/neovim/node-client/compare/v5.2.1...v5.3.0)
 

packages/neovim/src/utils/findNvim.ts

@@ -67,7 +67,7 @@ export type FindNvimResult = {
 };
 
 const versionRegex = /^(\d+)\.(\d+)\.(\d+)(?:-(.+))?$/;
-const nvimVersionRegex = /^NVIM\s+v(.+)$/m;
+const nvimVersionRegex = /^[nN][vV][iI][mM]\s+v?(.+)$/m;
 const buildTypeRegex = /^Build\s+type:\s+(.+)$/m;
 const luaJitVersionRegex = /^LuaJIT\s+(.+)$/m;
 const windows = process.platform === 'win32';