[3.0] Theme split (wave 1, part 2) — List the maintenance tasks as one pick-one form

[albertlast]

Wave 1, part 2 of breaking up #7933. Touches one theme template, and it is the one the change is about.

What changes

template_maintain_routine() and template_maintain_database() each hand-wrote a heading, a form and a submit button for every task. Adding a maintenance task meant editing the template. Both are replaced by one template_maintain_options():

foreach (Utils::$context['options'] as $activity => $option) {
	// radio + maintain_<activity> + maintain_<activity>_info
}

Utils::$context['options'] is built from the sub-action's own activities list, so the form and the dispatcher cannot drift apart. A task whose strings are not named maintain_<activity> supplies its own title and info, and after appends markup below the description. The shared wrapper and the "task finished" notice move into a maintain template layer.

Fixes the reported template error

@dragomano reported this on #7933:

Unable to load the '' template at Forum Maintenance - Routine

routine and database are the two sub-actions with no 'template' key, and the dispatcher did

Utils::$context['sub_template'] = !empty(self::$subactions[...]['template']) ? ... : '';

so they asked for a sub-template named ''. They now default to maintain_options.

Language strings

• maintain_errors → maintain_repair, so it matches its activity name. Its only consumer was the template being replaced.
• maintain_cache keeps its name — Admin.template.php and cleanCache() also use it — so cleancache supplies its title and info explicitly. Same for convertentities, since template_convert_entities() still uses the entity_convert_* strings.
• Adds text_title. Converting the messages body column is offered in both directions now, and the TEXT direction had no heading.
• Adds convert_to_suggest_text, shown when the maximum message length is at or above 65535, since shrinking the column would truncate posts members can currently make.

Note on scope

#7933 also converts the board picker on the Topics tab to <details> plus a shared template_choose_boards() helper. I left that out, for two reasons: the helper lives in GenericControls.template.php, which belongs to the editor part of the split, and it emits name="brd[]" while TopicRemove::old() reads $_POST['boards'] as an associative array — so on that branch, pruning by selected boards would not do what the form says. That conversion should come with the part that owns the helper, with the field name sorted out.

Testing

• Routine tab: all six tasks render with real strings, no unresolved language keys.
• Database tab on PostgreSQL: optimize and convertentities only, convertmsgbody correctly absent.
• Ran "Recount all forum totals and statistics" through the new form — task executes, the confirmation notice renders, and #manage_maintenance appears exactly once.
• Members, Topics and Integration Hooks tabs all still render; they do not use the new layer.
• 108/108 unit tests pass.

🤖 Generated with Claude Code

[live627]

• Some code that was removed in [3.0] Remove convert to text option #8787 has resurfaced.

[albertlast]

should be better now