[SPIKE] Departmental headers

[NickColley]

I have forked version 5.13.0 to allow Mia to look at the old branded headers again.

[github-actions]

📋 Stats

File sizes

File	Size	Percentage change
dist/govuk-frontend-development.min.css	119.87 KiB	7.4%
dist/govuk-frontend-development.min.js	45.83 KiB	3%
packages/govuk-frontend/dist/govuk/all.bundle.js	99.18 KiB	1.5%
packages/govuk-frontend/dist/govuk/all.bundle.mjs	93.21 KiB	1.5%
packages/govuk-frontend/dist/govuk/all.mjs	1.22 KiB	4.6%
packages/govuk-frontend/dist/govuk/govuk-frontend.min.css	119.86 KiB	7.4%
packages/govuk-frontend/dist/govuk/govuk-frontend.min.js	45.82 KiB	3%
packages/govuk-frontend/dist/govuk/init.mjs	7.26 KiB	0.9%

Modules

File	Size (bundled)	Percentage change (bundled)	Size (minified)	Percentage change (bundled)
all.mjs	87.18 KiB	1.6%	43.55 KiB	2.9%
character-count.mjs	22.94 KiB	-0.8%	9.74 KiB	-1.2%
service-navigation.mjs	7.41 KiB	-11.5%	3.44 KiB	-3.3%
header.mjs	6.65 KiB	New file	3.34 KiB	New file

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Action run for 0ab945d