remove under construction banner and note

[corporate-gadfly]

Checklist

I have:

• read the CONTRIBUTING.md document
• read and accepted the Developer Certificate of Origin document and added a Signed-off-by annotation to each of my commits
• read and accepted the AI Policy document and added Generated-by or Assisted-by annotations to each of my commits created with the help of an AI agent
• tested this code
• included documentation (including possible behaviour changes)
• documented the code
• added or modified regression test(s)
• added or modified unit test(s)

[miharp]

Please don't delete layout_end.html entirely — it also contains the syncSidebarNavGroups logic from f888334, which keeps the persistent sidebar in sync with the current collection during Turbo navigation.

[corporate-gadfly]

Please don't delete layout_end.html entirely — it also contains the syncSidebarNavGroups logic from f888334, which keeps the persistent sidebar in sync with the current collection during Turbo navigation.

@miharp Oops... Thanks for pointing that out. Could you take another look please?

[miharp]

LGTM, +1

[corporate-gadfly]

Banner was initially introduced in #49 but since then other changes were made to layout_end.html in #109 (which we are keeping).