(or ?id=) * POST /wp-json/agentsia/v1/seo-meta/ * { "title": "...", "description": "...", "noindex": true|false|"default", "canonical": "https://...", * "schema_jsonld": "{\"@context\":\"https://schema.org\", ...}" } * * Authenticated with the Application Password the site owner gave Agentsia. Writing requires the * `edit_post` capability on that very post. A field left out (or null) is not touched. An empty string * (title, description, canonical) or "default" (noindex) removes the custom value, so the SEO plugin * falls back to its own settings. * * The POST response is a fresh read of the stored values: the backend compares it with what it asked * for and never reports a change that did not land. * * Without any SEO plugin, the values are stored by this plugin and printed by it (`