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/changes/activity-stats/design.md

@@ -1,66 +0,0 @@
-## Context
-
-Activities store `distance` (m), `duration` (s, elapsed), `elevationGain/Loss`
-(m), `startedAt`, and `gpx`. Routes store distance + elevation. The three
-surfaces that render these (feed, detail, profile) each hand-roll their own
-markup and pick a different subset. There is no shared formatter and no derived
-pace/speed.
-
-## Goals / Non-Goals
-
-**Goals**
-- One presentation component and one set of formatting/derivation helpers.
-- Add average pace/speed and moving-vs-elapsed time as first-class headline
-  metrics.
-
-**Non-Goals**
-- No imperial/metric toggle in this change — render metric (km, m, km/h, min/km)
-  as the baseline; a units preference is a separate future change.
-- No per-point analytics charts (that's `journal-elevation-profile`).
-- No schema or API changes; everything is derived from existing fields.
-
-## Decisions
-
-### D1: One `StatRow` component
-A presentational `StatRow` takes an ordered list of `{ value, label, unit }`
-items and renders the shared layout (value prominent, small caption beneath,
-even spacing). Feed/detail/profile pass the items they have; the component never
-fetches. A `formatStat` helper centralizes number/unit formatting and goes
-through i18n.
-
-### D2: Canonical headline set
-The headline set, in order, is: **distance · time · avg pace/speed · ascent ·
-descent**. Surfaces may render a subset (e.g. the compact feed card may show
-distance · time · pace), but never reorder or relabel — the subset is a prefix
-or documented selection of the canonical set.
-
-### D3: Average pace vs. speed (sport-aware)
-`avgSpeed = distance / movingTime` (fallback elapsed). Presentation chooses:
-- **pace** (min/km) for foot sports (`hike`, `walk`, `run`),
-- **speed** (km/h) for wheeled/ski sports (`ride`, `gravel`, `mtb`, `ski`),
-- default to **speed** when sport type is unset.
-This depends on `activity-sport-type`; if that field is absent the rule still
-resolves (speed).
-
-### D4: Moving vs. elapsed time
-- **Elapsed** = stored `duration`.
-- **Moving** = derived from GPX trackpoint timestamps by summing inter-point
-  intervals and excluding intervals where the athlete is effectively stationary
-  (below a small speed threshold, e.g. < 0.5 m/s, with a max-gap guard). The
-  derivation lives in `@trails-cool/gpx` as a pure, unit-tested helper.
-- When the GPX has no trackpoint timestamps (planned routes, some imports),
-  moving time is unavailable and only elapsed is shown.
-
-### D5: Formatting
-`formatStat` formats distance (km, 1 decimal < 100 km), elevation (m, integer),
-time (h:mm or m:ss), speed (km/h, 1 decimal), pace (m:ss /km). Labels and unit
-suffixes come from `journal.stats.*` i18n keys (en + de).
-
-## Risks / Trade-offs
-
-- **Moving-time heuristic**: stop detection is approximate; the threshold is a
-  single documented constant in the gpx helper, tunable later. When in doubt we
-  fall back to elapsed, so we never show a moving time longer than elapsed.
-- **Subset discipline**: allowing surfaces to render a subset risks drift; the
-  canonical order + a shared component keeps it in check, and the spec forbids
-  reordering/relabeling.