Vendor Tailwind and daisyUI in the repo; never reach github.com

Builds used to download the Tailwind binary and the daisyUI plugins from GitHub
releases. They are now committed in tools/tailwind/:
- the Tailwind 4.3.3 standalone binary for linux-x64, xz -9e compressed (28 MB);
- daisyui.mjs and daisyui-theme.mjs 5.7.47;
- daisyUI's llms.txt component reference;
- Tailwind's MIT license.

tools/tailwind.sh no longer touches the network. "prepare" checks every file
against its pinned sha256 and unpacks the binary into .tools/. MSBuild reruns it
only when the archive or the script changes. A build from scratch was checked
inside a network namespace with no network at all.

.gitattributes keeps the vendored files byte-exact, and Tailwind no longer scans
tools/, whose llms.txt names every daisyUI class.

Both workflows used actions/checkout, which a Gitea runner downloads from
github.com. They now git fetch the commit from this Gitea, as they already did
for SocialPub.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LsXgEaXee4GCU1hwYgPJXw

tools/tailwind/LICENSE-tailwindcss

@@ -0,0 +1,24 @@
+Applies to tailwindcss-linux-x64.xz, the Tailwind CSS standalone executable (https://tailwindcss.com).
+daisyui.mjs and daisyui-theme.mjs carry their own MIT license at the end of each file.
+
+MIT License
+
+Copyright (c) Tailwind Labs, Inc.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.