max / makenotwork

Stop base.html and the page templates emitting the same head tags twice base.html emitted og:site_name, og:type and twitter:card before {% block head %}, and nine page templates emitted their own on top. Every item page carried og:type as both website and product, every post as both website and article, and the project pages carried twitter:card as both summary_large_image and summary. Base's copy came first, so a consumer taking the first occurrence read the generic value and the page's real one never won. og:type and twitter:card become blocks with base's generic value as the default; the nine pages override the block instead of restating the tag. Where the card was entangled with og:image inside a conditional, the whole conditional moves into the social_card block rather than duplicating the condition. og:site_name was seven identical copies and is now base's alone. Sealed by tests/head_meta_seal.rs, which reads the templates and fails on any child of base.html restating an owned tag outside its block. There was no test anywhere in the tree mentioning these tags, which is why this stood. Also drops db::items::media::update_item_cover_image_url. It set cover_image_url without touching cover_s3_key, the same url/key drift removed from the project side in 3e3b1d15, and it had no callers anywhere in the tree. update_item_cover is the live path and writes url, key and size together under a CAS. Every remaining writer of either column now moves both.