Follow-up of https://github.com/zed-industries/zed/pull/43854
Closes https://github.com/zed-industries/zed/issues/40970
Seems that json language server does not distinguish between JSONC and
JSON files in runtime, but there is a static schema, which accepts globs
in its `fileMatch` fields.
Use all glob overrides and file suffixes for JSONC inside those match
fields, and provide a grammar for such matches, which accepts trailing
commas.
Release Notes:
- Improved JSONC trailing comma handling