fix: Retrigger visibility completion after parentheses
close#12390
This PR add `(` to trigger_characters as discussed in original issue.
Some questions:
1. Is lsp's `ctx.trigger_character` from `params.context` is the same as `ctx.original_token` inside actually completions?
1. If not what's the difference?
2. if they are the same, it's unnecessary to pass it down from handler at all.
3. if they are the same, maybe we could parse it from fixture directly instead of using the `check_with_trigger_character` I added.
2. Some completion fixtures written as `($0)` ( https://github.com/rust-lang/rust-analyzer/blob/master/crates/ide-completion/src/tests/fn_param.rs#L105 as an example), If I understand correctly they are not invoked outside tests at all?
1. using `ctx.original_token` directly would break these tests as well as parsing trigger_character from fixture for now.
2. I think it make sense to allow `(` triggering these cases?
3. I hope this line up with #12144
e4ead8a7c6