[benchmark] Rerun Minimal Context delivery benchmark

[Seven128]

Prepare and run fresh Minimal Context benchmark passes before making any delivery-speed claims.

Acceptance signals:

• Uses the current Minimal Context Harness package, not historical stage-based workflow data.
• Keeps raw one-off outputs in temporary artifacts, not project_context/**.
• Publishes methodology and result boundaries before publishing conclusions.
• Separates context recoverability evidence from product quality evidence.
• Updates docs/launch/market-map.md or README only with claims supported by fresh runs.

Non-goal:

• Do not restore stage artifacts or phase gates as default package behavior.