[paulbalandan]

Description
Prepares five user guide tables for the Markdown migration (codeigniter4/docs-update). pandoc writes a Markdown pipe table only when every cell holds inline text, so these five came out as raw HTML.

• installation/upgrade_migrations.rst: removed a stray leading space in a header cell.
• database/configuration.rst: moved the note, the important block and the dateFormat key list out of the table and right below it.
• libraries/validation.rst: aligned the description column with its border.
• models/model.rst: folded the first()/find()/findAll() sub-rows into the beforeFind cell.
• outgoing/view_parser.rst: aligned the arguments column, and wrote the examples and HTML tags as inline literals.

No content is dropped. The strict Sphinx build passes. When merging into 4.8, database/configuration.rst conflicts, because 4.8's table is wider and has a timezone row. Resolve it the same way, moving the timezone values below the table.

Checklist:

• Securely signed commits
• Component(s) with PHPDoc blocks, only if necessary or adds value (without duplication)
• Unit testing, with >80% coverage
• User guide updated
• Conforms to style guide