feat(hikes): route-builder, overview map + cards, SAC-coloured pipeline

Build pipeline (scripts/build-hikes.ts) parses per-hike GPX, encodes
images via sharp, reverse-geocodes the centroid against Swisstopo and
emits a typed manifest under src/lib/data/hikes.generated.ts (gitignored).
Track JSON + image binaries live outside /static; served in dev by a
small hike-images plugin in vite.config.ts, in prod by nginx (private/
images proxied through Node + X-Accel-Redirect for auth-gating).

/hikes overview: full-bleed Swisstopo hero map (HikesOverviewMap) sits
under the sticky nav, drawing one polyline per route coloured by SAC
tier (T1 yellow Wegweiser, T2/T3 white-red-white, T4-T6 white-blue-
white). Click navigates, hover thickens + tooltips. Layer toggle,
recenter, GPS controls mirror the detail map (minus images toggle).
Cards drop the trail SVG, gain a per-route icon + SAC marker
pictogram on the cover, altitude range, season label, and "Neu" badge
for recently-published hikes. Filter bar + totals strip recompute over
the currently-visible set.

/hikes/[slug]: hero map with elevation profile, photo strip with map
sync, scroll-position pin, GPX download, SAC marker stats + min/max
altitude + season.

Route-builder (/hikes/route-builder): client-side draft persisted to
localStorage, EXIF-driven image placement, snap-to-route via BRouter
(OSRM + linear fallback) and Swisstopo profile.json elevation
enrichment that handles degenerate same-coord segments via the height
endpoint.

Filter init switched from a script-time snapshot of data.hikes (which
sporadically returned a one-hike subset during dev hydration and
locked the page to that single hike) to a post-mount \$effect.

Content under src/content/hikes/ intentionally not included (WIP).

.gitignore

@@ -15,6 +15,21 @@ data/usda/
 # Loyalty-card barcodes (regenerated by scripts/generate-loyalty-cards.ts from env)
 static/shopping/supercard.svg
 static/shopping/cumulus.svg
+# Hikes build outputs (regenerated by scripts/build-hikes.ts at prebuild)
+static/hikes/
+hikes-assets/
+src/lib/data/hikes.generated.ts
+# Build-script disk caches (Swisstopo identify, BRouter responses, ...)
+scripts/.cache/
+# Loose working-tree scratch files (notes, photos, prototypes) that aren't
+# part of the committed source.
+/HIKES_PLAN.md
+/additional_apologetics.md
+/header_jellyfin.html
+/person-hiking.svg
+/PXL_*.jpg
+/PXL_*.MP.jpg
+src-tauri/icons/_safezone_template_*.png
 src-tauri/target/
 src-tauri/*.keystore
 # Android: ignore build output and caches, track source files