openspec: archive the detail catch-up changes, sync specs

Archive the three implemented + merged changes (activity-sport-type,
activity-stats, journal-elevation-profile): their deltas are promoted into
openspec/specs/, the changes move to changes/archive/2026-06-12-*, and the
three new capabilities are added to the CAPABILITIES index.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

openspec/CAPABILITIES.md

@@ -65,6 +65,9 @@ When adding a new spec, slot it into the most relevant group below and update th
 ## Journal landing & content
 
 - [`journal-landing`](specs/journal-landing/spec.md) — anonymous landing + signed-in personal dashboard.
+- [`activity-sport-type`](specs/activity-sport-type/spec.md) — sport/activity-type enum on activities (set on create or normalized on import), shown as a badge + feed verb, federated as a Note PropertyValue.
+- [`activity-stats`](specs/activity-stats/spec.md) — the canonical headline metric set + reusable stat row (sport-aware avg pace/speed, moving-vs-elapsed time) across feed, detail, and profile.
+- [`journal-elevation-profile`](specs/journal-elevation-profile/spec.md) — read-only elevation profile chart + chart↔map "active distance" hover/click sync on the route & activity detail pages.
 - [`legal-disclaimers`](specs/legal-disclaimers/spec.md) — Terms / Privacy / Imprint pages.
 - [`transactional-emails`](specs/transactional-emails/spec.md) — magic-link, welcome, etc. email templates.
 - [`demo-activity-bot`](specs/demo-activity-bot/spec.md) — synthetic-content bot (Bruno by default) seeded for demo instances; configurable persona, retention, and seed region.