This patch migrates the previously separately managed helm chart into
this monorepo in order to profit from the already existing, unified
setup for chart and repository updates, as well as making sure, that
things keep being maintained.

This patch renames a bunch of service accounts and role bindings, that
were previously individual to the namespace, now using `flux-reconciler`
everywhere with idential permissions.

Further adjustments needed to make it a shared resource, currently the
requirement to have the namespace in the rolebinding makes this hard.
Have to investigate.

This patch removes the component label, which was previously manually
added by our deployment, but is now part of the helm chart.

This patch should fix nextcloud's own wrong perception of being
available over http instead of https.

This patch reduces the number of read-only replicas from 3 to 1 since
nextcloud doesn't need that many by default.

This patch removes the modsecurity feture for nextcloud, since it causes
quite heavy load on the machines. It might be a good idea to revisit
this later.

This reverts commit 007afae6.

This patch enables mod security for nextcloud and sets up the default
exceptions maintained by the CRS maintainers.

References:
https://github.com/coreruleset/coreruleset/blob/554fb063c2613ca9cb470524c721476c2eedf62f/rules/REQUEST-903.9003-NEXTCLOUD-EXCLUSION-RULES.conf