Implementation Plan
Covers Stage 7, IMPLEMENTATION_PLAN (docs/PROCESS_CONTRACT.md §5). Per
that stage's Approval Gate, Tech Lead sign-off is required for
medium/high-risk work; low-risk, template-covered work may use a
pre-approved Skill in place of a per-instance approval — recorded as an
explicit exception (docs/PROCESS_CONTRACT.md §8), never a silent skip.
Rejection path
Escalated to solution-design's stage, STORY_LLD, if the plan reveals
the design is unworkable (docs/PROCESS_CONTRACT.md, stage
IMPLEMENTATION_PLAN).