feat(notifications): allow configurable date/time format via env - #5578

What is this PR about?

Notification messages (Telegram, Slack, Discord, Mattermost, Lark, email, etc.) format dates with format(date, "PP") / format(date, "pp") from date-fns without a locale, so times always render in 12-hour US style (e.g. 1:49:41 PM). Users outside the US have no way to get 24-hour time or a local date format.

This PR adds two optional environment variables:

How

• New helpers in utils/notifications/utils.ts: formatNotificationDate, formatNotificationTime, formatNotificationDateTime.
• All format(date, "PP" | "pp" | "PP pp") calls in the notification senders now use these helpers (build-error, build-success, database-backup, docker-cleanup, dokploy-backup, dokploy-restart, volume-backup).
• No behavior change by default: without the env vars the output is identical to today.
• An invalid pattern falls back to the default instead of throwing, so a typo can't break notifications.

Usage

docker service update \
  --env-add NOTIFICATIONS_TIME_FORMAT=HH:mm:ss \
  --env-add NOTIFICATIONS_DATE_FORMAT=dd/MM/yyyy \
  dokploy

Happy to move this to a setting in the UI instead if you prefer that approach.

Checklist

Before submitting this PR, please make sure that:

• You created a dedicated branch based on the canary branch.
• You have read the suggestions in the CONTRIBUTING.md file https://github.com/Dokploy/dokploy/blob/canary/CONTRIBUTING.md#pull-request
• You have tested this PR in your local instance. If you have not tested it yet, please do so before submitting. This helps avoid wasting maintainers' time reviewing code that has not been verified by you.

Opened as draft until it's tested on a local instance. biome check passes on the changed files.

Issues related (if applicable)

N/A

Screenshots (if applicable)

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