Prefill "Working days" based on availability and public holidays

[jancborchardt]

"Working days" are prefilled

• Based on days of the week the person is working as well as public holidays (see below for logic)
• Can be overridden manually

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Extra settings added

Yes I know. ;) But in this case it had to be done because autodetecting helps a lot but maybe needs to be adjusted (and if so, usually only a single time).

Working days

• Tries to get those from "Availability" if specific days are set
• Uses Mon–Fri as reasonable default otherwise
• In case "Availability" is not set, people are also prompted to add it as it is useful in general
• Can be overridden manually

Public holidays

• Gets holidays based on location. date-holidays is lazy-loaded, so the main bundle is unchanged, and the holiday data is a separate chunk loaded only when needed.
• Country is inferred from profile (if set) or phone number (if set)
• Can be overridden manually and/or specified in detail, like for German states

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🤖 AI (if applicable)

• The content of this PR was partly or fully generated using AI