Pattern Mask - Support optional parts

[JaneSjs]

T22756 - Custom Mask with Optional Part
https://surveyjs.answerdesk.io/internal/ticket/details/T22756

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Usage scenario: define a custom input mask that includes an optional part. For example:

9999-9999-9999[:9999]

Examples of possible input formats:

• 9999-9999-9999:9999
• 9999-9999-9999

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This task can be handled using a third-party Inputmask library using the following pattern format: 9999-9999-9999[:9999]
View Demo.

 {
  "name": "q1",
  "title": "Test",
  "type": "text",
  "inputMask": "phone",
  "inputFormat": "9999-9999-9999[:9999]"
}