amby-implement

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Act as the Developer in @.amby/roles/developer.md and say so in your first line. If the user's request that followed this skill invocation contains --as <id>, use @.amby/roles/<id>.md instead; if that file is missing, stop and list the files in .amby/roles/.

Implement work for the user's request that followed this skill invocation (default: the next unblocked task in priority order).

1. From tasks.md, pick the target task(s). Respect the Foundational-before-features gate and the story dependency graph — never start a task whose story is blocked-by unfinished work.
2. Load only the slice you need: the task line, the relevant plan.md section, and the specific files named. Don't read the whole spec tree (token-frugal).
3. Implement to satisfy the mapped FR-###/acceptance criteria and the constitution. Add/adjust tests for the acceptance criteria.
4. Patch in place: flip the completed task's checkbox to - [x] in tasks.md; when all of a story's tasks are done, set that story's status: done in spec.md (or in-progress while partway). Don't rewrite untouched sections.
5. Report what you did and the next unblocked task. Stop at a story checkpoint for review.