site: cut the template's own labels out of the pages

Point 7 of the page-wording review. The pages no longer show their data
structure as headings, and they no longer explain their own conventions.

- Level 1 is one screen: claim, status badge, three figures, the technology
  row, and one sentence carrying one link. Measured in headless Chrome at
  1440x900: 1404-1845 px tall before, exactly 900 px (no scroll) after, on
  all six area pages.
- DocPage: no kicker line, no visible level label, no "Evidence for this
  page" heading or instruction note, no "Drill-downs" list, no
  "Status <word> - sentence" footer. The artefact table starts at level 2,
  under the heading "Artefacts"; the history timeline is level 2 only.
- Landing page: "Start here" link text gone, "How to read this site" panel
  gone, the footer's status-label explainer gone.
- Content, presentation only, no claim softened: the leading H1 that
  duplicated the page title removed from all 41 documents; level 1 bodies
  reduced to the constraint as ordinary prose plus the way in;
  "**Status: ...**" prefixes removed from the artefact stubs; "## Drill-downs"
  and "## Period and confidence" removed from the level 2 pages, with the
  cross-area links moved into the prose.
- The six level 1 claims are now sentences with a subject, and use commas
  instead of middots. Same facts, no new ones.

Not in this commit: the 35 level 2 and 3 claims still use the compact CV
style. That is a voice decision for Sam, not a wording tidy-up.

make validate: 41 documents, 0 violations. go test ./...: pass.

(cherry picked from commit 03009f80fc7815ad7719412e125df9297a6e653f)

internal/web/static/site.css

@@ -600,11 +600,6 @@ samp {
 	color: var(--text-muted);
 }
 
-.pillar-go {
-	font-weight: 600;
-	border-bottom: 0;
-}
-
 .pillar-count {
 	font-family: var(--font-mono);
 	font-size: 0.74rem;
@@ -658,28 +653,6 @@ samp {
 	color: var(--text-dim);
 }
 
-.honesty {
-	padding: 1.2rem 1.4rem;
-	background: var(--surface);
-	border: 1px solid var(--line);
-	border-left: 3px solid var(--accent);
-	border-radius: var(--radius);
-}
-
-.honesty h2 {
-	margin-top: 0;
-	font-size: 1.05rem;
-	text-transform: uppercase;
-	letter-spacing: 0.08em;
-	color: var(--text-dim);
-}
-
-.honesty ul {
-	margin: 0;
-	padding-left: 1.1rem;
-	color: var(--text-dim);
-}
-
 .doc-head {
 	padding-bottom: 1.1rem;
 	border-bottom: 1px solid var(--line);
@@ -1289,7 +1262,6 @@ figure.media figcaption {
 	.hero,
 	.pillar,
 	.result,
-	.honesty,
 	.drill-list li,
 	.stage,
 	.prose blockquote {