Optimise - remove unused core functions. Document filtering & columns.

[EarthlingDavey]

• Remove unused WordPress core functions, using filters and actions.
• Filtering and columns on document post type. Useful for identifying documents without attachments or revisions.
• Trial phpdocs in /inc/documents folder.

[EarthlingDavey]

Composer install is breaking the build so this commit also includes a fix.

The current dockerfile:

COPY ./composer.json /var/www/html/composer.json
RUN composer install --no-dev --no-scripts --no-autoloader

COPY . .
RUN composer install --no-dev

• Installs the newest version for any package when the version is set to '*', e.g. debug-bar.
• Then COPY . . will copy the composer.lock file.
• The 2nd composer install will install the locked versions. Which may be behind latest
• Sometimes the 2nd install will need to remove a file, and it fails at this step.

The issue... can be seen on this workflow https://github.com/ministryofjustice/justice-gov-uk/actions/runs/8325274173/job/22778565139 or locally with the command docker build . --target=build-nginx

The change.

• Copy composer.json and composer.lock and run composer install once.
• Don't run COPY . . in build-fpm-composer and adjust build-fpm & build-nginx accordingly.

[EarthlingDavey]

Following yesterdays chat, package versions have been defined approptiately.

Also, it the interest of minimising the surrfce for vulnerabilities, sentry/sdk has been removed because we use sentry/sentry. The env function of oscarotero/env has been brought n house.