Recurring tasks and task dependencies

[th3-br41n]

Tasks that repeat on a schedule, tasks that block other tasks, and a workload view over the result.

Three related pieces:

• Recurring tasks — a weekly review that regenerates rather than being copy-pasted, with the recurrence rules the Calendar already understands.
• Dependencies — "this cannot start until that is done", expressed as a typed relation so Graph and Database can both see it.
• A workload view — what is actually on you across projects, rather than per-project lists you have to hold in your head.

Dependencies here are the same relation the Database timeline view uses, so the two land on one model rather than two.