- Add the secret-zero bootstrap-chain diagram (was a broken image ref)
- Remove the corner sparkle artifact from all six blog hero images
- Bump hero/diagram cache-bust params so the updated assets serve
outbound-only-exposure (corrected sealed-vault image) + secret-zero (the seed-
key circuit-tree, _R revision). Both verified against their prompts, optimized
to webp (17KB / ~120KB). Completes hero coverage for all 6 posts.
jwright
