Blueprint: thorough, validation-first planning

The point is not a longer plan. The point is to refuse to commit to a plan until the assumptions under it have been tested against reality. /plan says "here is how I would build it". /blueprint adds why each load-bearing assumption holds, with the evidence. A cheap experiment beats confident reasoning, and the source on HEAD beats memory.

Do not invoke it for typo fixes, single-file edits, or mechanical renames. This skill is expensive on purpose.

Required references

Paths are relative to this file. <plugin root> is two directories above it. Read each file at the step named.