Semantic highlighting API draft should incorporate "importKeyword" and "modifierKeyword" token types

https://github.com/microsoft/vscode-languageserver-node/blob/e5d7ad881b1a51b486e3f0e4aa0fbc25dad2be58/protocol/src/protocol.semanticTokens.proposed.ts#L18 < this appears to be the basis for the latest semantic highlighting draft, and I was asked I make a separate ticket for this:

• I think some import/include/require token is super common (and while it might be a function in some languages it's a special dedicated keyword in many others) and therefore I suggest an "import" keyword is added to the default built-in list of the spec. Whether themes use it I don't really mind, but I just suggest it should be available for sending through the LSP server

• the modifier list IMHO should include an "other modifier" type. For any remotely unusual language there's bound to be modifiers not covered by this list, and it would be still very useful info for a language client's themeing to know it's a modifier (rather than whatever generic keyword)

Start with protocol/src/protocol.semanticTokens.proposed.ts at the linked token-type and modifier-list definitions, then read the linked Language Server Protocol draft issue and referenced discussion. Determine whether the proposed import and additional modifier categories fit the current draft; done means the agreed semantic-token specification reflects the decision.