Feature request: Customizable agenda scheduled/deadline prefix text

[bezark]

Feature Request

Allow users to customize or remove the "Scheduled:" and "Deadline:" prefix text in the agenda view.

Problem

The repeated "Scheduled:" text adds visual clutter, especially when viewing many items:

Day-agenda for Saturday:
Saturday    08 February 2025
  Work:       09:00 ------------ Scheduled: Team standup
  Work:       10:00 ------------ Scheduled: Code review
  Work:       14:00 ------------ Scheduled: TODO Fix login bug
  Personal:   15:00 ------------ Scheduled: Dentist appointment
  Home:       18:00 ------------ Scheduled: TODO Grocery shopping
  Home:       19:00 ------------ Deadline:  TODO Pay rent

The word "Scheduled" appears 5 times and doesn't add useful information - users already know these are scheduled items because they're in the agenda.

Proposed Solution

With customizable prefixes, users could achieve a cleaner view:

Day-agenda for Saturday:
Saturday    08 February 2025
  Work:       09:00 ------------ Team standup
  Work:       10:00 ------------ Code review
  Work:       14:00 ------------ TODO Fix login bug
  Personal:   15:00 ------------ Dentist appointment
  Home:       18:00 ------------ TODO Grocery shopping
  Home:       19:00 ------------ ! TODO Pay rent

Add configuration options similar to Emacs org-mode:

require('orgmode').setup({
  -- Remove scheduled prefix entirely
  org_agenda_scheduled_leaders = {'', ''},
  -- Keep deadline visible with short prefix
  org_agenda_deadline_leaders = {'! ', '! '},
})

This would give users control over their agenda density while maintaining compatibility with existing behavior as the default.

Thank you for the excellent plugin!