/speckit.tasks — break the plan into executable tasks

Gate: the current feature needs a filled plan.md — read spec.md and plan.md before writing anything; if plan.md is missing, stop and say so.

Run python3 speckit.py tasks — it seeds tasks.md for the current feature (refused while plan.md is missing).
Replace the placeholder checkboxes with real tasks: dependency-ordered phases under ## Phases, one checkbox per task, exact file paths in each description, user-story order preserved (P1 first).
Every task must be small enough to verify on its own; note which tasks are independent enough to run in parallel.
Run python3 speckit.py status to see the open-task count.