[Feature request] Add JSON5 support

[sXNA]

Could you add JSON5? Currently only comments work.

[rdipardo]

A link to a language spcification is needed here, to avoid the misunderstanding that JSON5 is merely "JSON with comments": https://json5.org/#summary-of-features

The original downstream issue notes, for example, that single-quoted strings are lexed as errors: notepad-plus-plus/notepad-plus-plus#14992

[genieyr]

It's highlighted as red

lineBreaks: "Look, Mom! \
No \\n's!"

are there any news about implementation JSON5?

[pryrt]

Because there is no JSON5 option for Lexilla's JSON lexer, it also doesn't handle unquoted keys, which JSON allows.

And as a result, code folding is incorrect on JSON5 with unquoted keys (see this discussion in the Notepad++ forum; verified with SciTE 5.5.3/Lexilla 5.4.1 in that discussion). Here is the example JSON5 text:

    {
      key: 1,
      name: "更新提示",
      quickFind: true,
      matchTime: 10000,
      actionMaximum: 1,
      resetMatch: "app",
      activityIds: [
        "net.csdn.csdnplus.activity.MainActivity",
        "net.csdn.csdnplus.activity.SetActivity",
      ],
      rules: [
        {
          matches: "[id=\"net.csdn.csdnplus:id/update\"] -2 [id=\"net.csdn.csdnplus:id/cancel\"]",
          snapshotUrls: [
            "https://i.gkd.li/import/12673693",
            "https://i.gkd.li/import/12673654",
          ],
        },
      ],
      enable: false,
    }

... which only folds from line1 to line11 instead of line1 to line 22.