fix(en): support 'of' connector in weekday postfix modifier (e.g. 'Tuesday of next week')

[breissingerj]

Problem

ENWeekdayParser did not recognise the word of as a connector between a weekday and its postfix modifier (this/last/next week). The postfix group regex only allowed optional whitespace directly before the modifier keyword:

// before
"(?:\\s*(this|last|past|next)\\s*week)?"

As a result, any phrase of the form <weekday> of <modifier> week silently dropped the modifier and fell back to getDaysToWeekdayClosest(). When today is the named weekday (e.g. parsing "Tuesday of next week" on a Tuesday), the closest match is 0 days away — returning today instead of next week. Additionally, because the full phrase was not consumed as one token, adding a time component (e.g. "Tuesday of next week after 2pm") produced two separate results instead of one merged date-time.

Fix

Add (?:of\\s*)? as an optional non-capturing group inside the postfix:

// after
"(?:\\s*(?:of\\s*)?(this|last|past|next)\\s*week)?"

This accepts "Tuesday of next week", "Friday of last week", and "Wednesday of this week" while leaving all existing patterns ("next Tuesday", "Tuesday next week", "Tuesday, next week", etc.) completely unchanged.

Tests

A new test block — "Test - Weekday 'of next/last/this week' connector" — is added to test/en/en_weekday.test.ts with 10 cases covering:

• of next week for the same weekday as the ref date (the original edge case)
• of next week for earlier and later weekdays
• of last week for same and different weekdays
• of this week for the same and a forward weekday
• Combined with a time component (after 2pm, at 9am) — asserts a single merged result
• In-sentence context

All 519 tests pass (npm test).

[wanasit]

Thanks for the improvement!

[coveralls]

coverage: 92.482% (-0.03%) from 92.515% — breissingerj:fix/weekday-of-next-week-modifier into wanasit:master