MBS-6566: Load all release columns in load_with_medium_for_recording

A few of the release columns were never fetched in this query, which
meant that releases found via this method would never have a language,
script or barcode. I've added the columns (and re-organised them) so
this list matches `_columns`
MBS-6066: Deny edit relationship edits when link type has changed

When an 'edit relationship' edit is created, we log the link type
that it was created against. If the relationship later changes type,
we now fail any edits against a different type, as the context of
the edit has entirely changed.
MBS-6605: Fix the display of /isrc pages

By default, Controller::Role::Load will try to set
`$c->stash->{model_to_type($model)}` to the result of `_load`,
if `model_to_type($model)` is a valid mapping.

Previously, this wouldn't resolve to anything, and so this key
would remain unchanged. However, d234581098ebdd added mappings for
ISRCs and ISWCs, and so after `_load`, `$c->stash->{isrc}` was set to
the result of `_load` (which amusingly, was `$c->stash` itself).

In this commit, I have added another condition that must be met
for this default setting to occur - the absence of any value in
this key.
MBS-6596: Fix definedness check when showing release events

The country is not meant to be linked to if it is undefined, as
this means the release event doesn't have a country at all. However,
the country was defined, just empty. The check has been updated to
check for a true id value instead.
MBS-6442: Disallow /login to search engines
MBS-6494: Artist end area implies artist has ended

Add a trigger to set artist.ended to true when artist.end_area is a
non-null value.
MBS-6408: Add the s_release_event view

This view unions all release_country rows with release_unknown_country, in order
to make it easy to find all release events for a release.

I have also updated s_release, as that was refering to the now deleted
date/country columns.
Merge branch 'mbs-6408' into beta
Merge branch 'mbs-6494' into beta
Merge branch 'mbs-6442' into beta
Merge branch 'mbs-6606' into beta
Merge branch 'mbs-6605' into beta
Merge branch 'mbs-6566' into beta
Merge branch 'mbs-6596' into beta