Replace Tailwind CDN with pre-built CSS via standalone CLI

- Add shared/static/styles/tailwind.css as Tailwind v4 input with
  explicit @source paths for all service templates and safelisted
  dynamic classes (bg-{colour}-{shade}, text-{size})
- Build to shared/static/styles/tw.css (93KB minified)
- Replace <script src="cdn.tailwindcss.com"> with <link> to tw.css
  in sx page shell, Jinja _head.html, and ~base-shell component
- Add build-tw.sh convenience script

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

build-tw.sh

@@ -0,0 +1,9 @@
+#!/usr/bin/env bash
+# Build Tailwind CSS from source templates.
+# Requires: tailwindcss CLI standalone binary on PATH.
+#   curl -sL https://github.com/tailwindlabs/tailwindcss/releases/latest/download/tailwindcss-linux-x64 \
+#     -o /usr/local/bin/tailwindcss && chmod +x /usr/local/bin/tailwindcss
+set -euo pipefail
+cd "$(dirname "$0")"
+tailwindcss -i shared/static/styles/tailwind.css -o shared/static/styles/tw.css --minify
+echo "Built shared/static/styles/tw.css ($(wc -c < shared/static/styles/tw.css) bytes)"

shared/browser/templates/_types/root/_head.html

@@ -6,7 +6,7 @@
     <link rel="stylesheet" type="text/css" href="{{asset_url('styles/blog-content.css')}}">
     
     <meta name="csrf-token" content="{{ csrf_token() }}">
-    <script src="https://cdn.tailwindcss.com"></script>
+    <link rel="stylesheet" type="text/css" href="{{asset_url('styles/tw.css')}}">
     <link rel="stylesheet" href="{{asset_url('fontawesome/css/all.min.css')}}">
     <link rel="stylesheet" href="{{asset_url('fontawesome/css/v4-shims.min.css')}}">
     <link href="https://unpkg.com/prismjs/themes/prism.css" rel="stylesheet" />

shared/static/styles/tailwind.css

@@ -0,0 +1,30 @@
+@import "tailwindcss" source(none);
+
+/* Scan all template and component files */
+@source "../../../shared/sx/templates";
+@source "../../../shared/browser/templates";
+@source "../../../shared/static/scripts";
+@source "../../../blog/sx";
+@source "../../../blog/templates";
+@source "../../../market/sx";
+@source "../../../market/templates";
+@source "../../../cart/sx";
+@source "../../../cart/templates";
+@source "../../../events/sx";
+@source "../../../events/templates";
+@source "../../../federation/sx";
+@source "../../../federation/templates";
+@source "../../../account/sx";
+@source "../../../account/templates";
+@source "../../../orders/sx";
+@source "../../../orders/templates";
+
+/* Dynamic classes from ~menu-row-sx: bg-{colour}-{shade}
+   colour defaults to "sky", shade = 500 - (level * 100) for levels 0-4 */
+@source inline("bg-sky-{100,200,300,400,500}");
+@source inline("bg-stone-{100,200,300,400,500}");
+@source inline("bg-emerald-{100,200,300,400,500}");
+@source inline("bg-amber-{100,200,300,400,500}");
+
+/* Dynamic text size in ~status-pill: text-{sz} */
+@source inline("text-{xs,sm,base,lg}");

shared/sx/helpers.py

@@ -379,7 +379,7 @@ _SX_PAGE_TEMPLATE = """\
 <link rel="stylesheet" type="text/css" href="{asset_url}/styles/cards.css">
 <link rel="stylesheet" type="text/css" href="{asset_url}/styles/blog-content.css">
 <meta name="csrf-token" content="{csrf}">
-<script src="https://cdn.tailwindcss.com"></script>
+<link rel="stylesheet" type="text/css" href="{asset_url}/styles/tw.css">
 <link rel="stylesheet" href="{asset_url}/fontawesome/css/all.min.css">
 <link rel="stylesheet" href="{asset_url}/fontawesome/css/v4-shims.min.css">
 <link href="https://unpkg.com/prismjs/themes/prism.css" rel="stylesheet">

shared/sx/templates/pages.sx

@@ -10,7 +10,7 @@
           "body{margin:0;min-height:100vh;display:flex;align-items:center;"
           "justify-content:center;font-family:system-ui,sans-serif;"
           "background:#fafaf9;color:#1c1917}")
-        (script :src "https://cdn.tailwindcss.com")
+        (link :rel "stylesheet" :type "text/css" :href (str asset-url "/styles/tw.css"))
         (link :rel "stylesheet" :href (str asset-url "/fontawesome/css/all.min.css")))
       (body :class "bg-stone-50 text-stone-900"
         children))))