fix(seo,geo): I5 — disclose sampling coverage instead of implying an audit

Both agents sample (seo-analyzer.md:403 "sample 5-15 key pages",
geo-analyzer.md:460 "Sample 5-10 key pages") and neither states it. The
report says "audit". On a 500-page site a 12-page sample is 2.4%, and the
reader cannot know that unless it is printed. /client-handover gates on
these scores.

The denominator was already within reach: STEP 4 fetches sitemap.xml. Count
its URLs and the coverage ratio is free — same data C1 will use for
sitemap-driven crawl later.

- Mandatory COVERAGE line in both scoring blocks: N of M sitemap URLs (P%),
  or "total UNKNOWN" when no sitemap. Never omitted, never rounded up.
- seo: <25% coverage repeats in §0 as a major alert. Sample by risk (one
  page per template + GSC position 4-10 quick wins), name skipped templates
  — an un-sampled template is an un-audited template.
- geo: scoped honestly rather than blanket — COVERAGE bounds the per-page
  axes (Content Shape, page-level Schema.org) but NOT the site-wide ones
  (AI Crawlers Policy, llms.txt are single files, fully read). One ratio
  should not discredit axes it does not govern.

Verified: make test 35 GREEN / 0 RED.

agents/geo-analyzer.md

@@ -459,6 +459,12 @@ Load: `~/.claude/agents/resources/content-shape-for-ai.md`
 
 Sample 5-10 key pages (homepage + top service/blog pages). For each:
 
+**Record the denominator.** This samples; the report says "audit". Count the
+URLs in `sitemap.xml` for the coverage ratio, and carry it into the GEO
+SCORING block. No sitemap → total UNKNOWN, say so. Content shape is the
+axis most damaged by silent sampling: it is judged per page, so a 6-page
+sample of a 300-page site says nothing about the other 294.
+
 ### Checks
 
 1. **Definition Lead** — does the first sentence (or H1) follow
@@ -586,6 +592,7 @@ Score each axis. Use concrete findings from STEP 2-9.
 
 ```
 GEO SCORING (<depth>)
+COVERAGE                  : <N> of <M> sitemap URLs (<P>%) | <N> pages, total UNKNOWN
 AI Crawlers Policy        : XX/20  <justification>
 llms.txt                  : XX/20  <justification>
 Schema.org for AI         : XX/20  <justification>
@@ -596,6 +603,12 @@ AI Visibility (live)      : XX/20 | N/A (LOCAL)
 GEO GLOBAL (weighted)     : XX.X/20 (<depth>)
 ```
 
+**COVERAGE is mandatory, never omitted, never rounded up.** It bounds the
+per-page axes — Content Shape above all, and the page-level share of
+Schema.org. Site-wide axes (AI Crawlers Policy, llms.txt) are unaffected:
+robots.txt and llms.txt are single files, fully read. Say which is which
+rather than letting one ratio discredit the whole report.
+
 Per user instruction: **GEO weight in combined SEO+GEO report = 20% for
 local, 25% for national/SaaS/content.**