Double escaping in array builder

[lmorg]

Describe the bug:
Double escaping is required in array builder:

» %[[2024..2026]\\, [spring..winter]]
[
    "2024, spring",
    "2024, summer",
    "2024, autumn",
    "2024, winter",
    "2025, spring",
    "2025, summer",
    "2025, autumn",
    "2025, winter",
    "2026, spring",
    "2026, summer",
    "2026, autumn",
    "2026, winter"
]