feat: #3614639 Show the filter reset, and match the listing spacing and summary to the design

Follow-up to #3614639.

Problem

• The Reset link never appeared on the events filters. The exposed form plugin reads its own reset_button_always_show, while the view only set Better Exposed Filters' bef.general.reset_button_always_show. Core hides the reset action when there is no exposed input, so it stayed hidden.
• The result summary rendered at 18px in the body colour with no emphasis, against 16px in the navy text tone with the range in bold and 40px before the list.
• The listing grid used 24px gutters against 32px.
• The pager listed nine page links where the design shows a five-link window.
• The event card used a 16px corner radius against 20px.

Resolution, all on views.view.events unless noted

• Set the exposed form's own reset_button_always_show.
• Pager quantity 5.
• Grid utility classes gy-grid gx-grid on both the master display and block_1. The events page is a Canvas page placing the block_1 display, and block_1 overrides the master's style options, so setting the master alone changes nothing on the page.
• Result summary: 16px, navy tone, range in bold, 40px below.
• config/canvas.content_template.node.event.card.yml: the card's corner style moves to the 20px step.

Depends on the matching Vartheme BS5 Horizon Aid change, #3614638 / MR !12, which defines the 32px gutter step and makes the 20px radius step available. Land that one first.

Verified on a Varbase 11 site in a browser: Reset renders beside Apply Filters; the summary reads 16px in the navy tone with the range bold and 40px below; the card grid measures 32px between columns and rows; the card corner radius is 20px; zero render errors. The Canvas card template validates with zero violations.

AI-Generated: Yes

Checkpoints:

• File an issue
• Addition/Change/Update/Fix
• Testing to ensure no regression
• Automated unit testing coverage
• Automated functional testing coverage
• UX/UI designer responsibilities
• Readability
• Accessibility
• Performance
• Security
• Developer Documentation
• User Guide Documentation
• Reviewed by human
• Code review by maintainers
• Full testing and approval
• Credit contributors
• Review with the product owner
• Release notes snippet
• Release