SEO: improved titles for Skosmos 3 generated HTML pages

[osma]

Reasons for creating this PR

Improve search engine optimization in Skosmos 3 by making the <title> values and related metadata (title, twitter:title, og:title) conform to the specification in https://github.com/NatLibFi/Skosmos/issues/1533#issuecomment-2063290242 .

This PR only handles the titles, not descriptions. The descriptions will have to be implemented in a subsequent PR.

Link to relevant issue(s), if any

• Part of #1533

Description of the changes in this PR

• refactor: pass the GlobalConfig instance to the Twig templates, instead of individual configuration settings in separate variables
• adapt the Twig templates to use the GlobalConfig instance, and set their title metadata to match the specification
• add Cypress tests to verify the title values

Known problems or uncertainties in this PR

Checklist

• [x] phpUnit tests pass locally with my changes
• [x] I have added tests that show that the new code works, or tests are not relevant for this PR (e.g. only HTML/CSS changes)
• [x] The PR doesn't reduce accessibility of the front-end code (e.g. tab focus, scaling to different resolutions, use of .sr-only class, color contrast)
• [x] The PR doesn't introduce unintended code changes (e.g. empty lines or useless reindentation)

[sonarqubecloud[bot]]

Quality Gate failed

Failed conditions
54.1% Duplication on New Code (required ≤ 3%)

See analysis details on SonarCloud

[osma]

Converting back to draft, because I still need to:

• [x] add the missing "Error" msgid pointed out by @joelit
• [x] ~implement long title (skosmos:serviceNameLong setting) for the landing page~ (decided that this is out of scope for this PR)

[sonarqubecloud[bot]]

Quality Gate failed

Failed conditions
54.1% Duplication on New Code (required ≤ 3%)

See analysis details on SonarCloud