skills: add SEO/AEO audit and grounded-JSON-LD skills from citeworthyio/seo-agent

Evaluated citeworthyio/seo-agent for reusable process knowledge. Relevant
to this fleet's WordPress content sites (granja travel news, content-agent
pipeline): a crawl-diagnose-approve-recrawl-measure loop for SEO metadata
changes, a three-layer AI-crawler accessibility audit (robots policy, bot
delivery, readable content), and a fail-closed method for generating and
safely injecting Article JSON-LD. Keyword research and citation-probe
pieces of the source repo were skipped as underdeveloped or too
infra-coupled to be reusable here.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

skills/seo-change-lifecycle/SKILL.md

@@ -0,0 +1,86 @@
+---
+name: seo-change-lifecycle
+description: Use when auditing a content site's SEO, proposing metadata changes, or evaluating whether an applied SEO change helped. Treat findings as measured conditions and close the loop through approval, delivered-output verification, and delayed Search Console comparison.
+license: MIT
+source: adapted from https://github.com/citeworthyio/seo-agent/blob/b78bb487f2819c3c7cc2ba6f3f5626ea0b841840/README.md (How it works, Findings lifecycle, Analytics)
+---
+
+# SEO Change Lifecycle
+
+An SEO edit is not complete when source content changes. It is complete only
+after the served page is recrawled and the outcome has had time to emerge in
+search data. Use this loop for metadata and technical on-page changes.
+
+## 1. Snapshot what crawlers actually receive
+
+Start from the sitemap and fetch every listed final URL. Record the delivered
+status, title, meta description, canonical, robots directive, OpenGraph image,
+and JSON-LD types. Do not audit templates or CMS fields in place of the response:
+an edge rewrite, stale cache, redirect, or failed deployment can make the served
+page disagree with its source.
+
+If no usable sitemap exists, use a bounded, same-origin link crawl and label the
+result incomplete. A link crawl cannot find orphan pages, so absence from that
+sample is not evidence that a page does not exist.
+
+## 2. Diagnose deterministic conditions
+
+Prefer repeatable rules whose evidence can be preserved and checked again. At a
+minimum, inspect:
+
+- sitemap URLs returning errors or redirects;
+- missing titles, duplicate titles, and titles whose core exceeds 60 characters
+  or whose delivered total exceeds 80;
+- missing descriptions, descriptions shorter than 70 or longer than 160
+  characters, and descriptions ending in `...` because upstream truncation can
+  hide an over-long source value;
+- missing or off-page canonicals;
+- `noindex` pages still present in the sitemap;
+- missing `og:image` and missing `Article` JSON-LD on known article routes.
+
+Decode HTML entities before length checks so `&` counts as the one character a
+reader sees. Key each finding by `(path, rule)`: keep it open while the condition
+persists and auto-resolve it only when a fresh crawl no longer reproduces it.
+This makes findings sensors, not tickets someone can close without fixing the
+underlying page.
+
+## 3. Draft a constrained proposal
+
+Give a drafter the page's observed content, the exact failed rule, the current
+served value, and the site's positive style guidance. Require the smallest field
+change that can clear the finding. Use deterministic surgery when there is one
+right answer (for example, removing a duplicated brand suffix or replacing a
+canonical with the page's own normalized URL); a model adds risk without value.
+
+Validate model output outside the model. Reject an unchanged value, forbidden
+terms, a title that includes a suffix the publishing layer will append, or copy
+outside the agreed length and sentence constraints. An invalid proposal is no
+proposal, not a reason to relax the gate.
+
+## 4. Review, apply, journal, and recrawl
+
+Require human approval by default. Record the old value, approved value, field,
+path, timestamp, and a reversible change identifier. After applying, fetch the
+public URL again and compare the delivered field with the approved value. Keep
+the finding in an `applied, awaiting recrawl` state until that comparison passes.
+
+This extra verification catches the failures source inspection misses: a wrong
+cache key, route gap, stale CDN response, lost edge binding, or deployment that
+never reached the serving path. A successful write to a CMS or override store is
+not proof that crawlers see the change.
+
+## 5. Measure impact without claiming causation
+
+Use page-level Search Console data, not site-wide totals. Leave a three-day
+settling gap after the change, then compare equal 14-day before/after windows;
+repeat with 28-day windows when enough data exists. Compare clicks and
+impressions as per-day rates and CTR/position as impression-weighted averages.
+Do not calculate a verdict if either window is absent or the two windows total
+fewer than 50 impressions.
+
+Treat a relative CTR movement of about 15% or an average-position movement of
+about 1.0 as a review signal, with impression shifts checked for confounding.
+Call the result correlation, never causation: seasonality, algorithm changes,
+competitors, and query-mix changes remain plausible explanations. A negative
+signal should open a review/revert decision, not trigger an automatic rollback.
+