Cut climb profile sections in the backend

The chart steps are computed in Go and shipped as finished sections, next to
the profile statistics the climb package already owns: climb.ProfileSections
cuts a Route at its widest bends under a ProfilePolicy, and
rideanalysis.MergeClimbProfile takes over the merge that lived in
web/climbs.go, so web only loads the attempt rides and maps the DTOs.

The payload carries sections instead of raw elevations, and the browser keeps
what needs the canvas: slope bands, labels, distance ticks and colours.
official-climb-profile-logic.ts and its tests are gone, replaced by
climb/profile_test.go and a page test reading the embedded profile JSON.

1 files changed, 56 insertions, 0 deletions

diff --git a/rideanalysis/profile_test.go b/rideanalysis/profile_test.go
new file mode 100644
index 0000000..5fb0772
--- /dev/null
+++ b/rideanalysis/profile_test.go
@@ -0,0 +1,56 @@
+package rideanalysis_test
+
+import (
+	"testing"
+
+	"github.com/martinlehoux/biking_home/climb"
+	"github.com/martinlehoux/biking_home/internal/ridetest"
+	"github.com/martinlehoux/biking_home/official_climb"
+	"github.com/martinlehoux/biking_home/ride"
+	"github.com/martinlehoux/biking_home/rideanalysis"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestMergeClimbProfileMediansRecordedPassages(t *testing.T) {
+	parsed, officialClimb := attemptRideForClimb(t)
+	officialClimb.ID = 42
+	// Same trace 10 m higher: the merge must average the two passages, not pick one.
+	shifted := ridetest.MustRide("1km at 14.7% | 1km at -6.7%", ridetest.StartCoord(43.61, 5.42), ridetest.StartElevation(310), ridetest.Sampling(1000), ridetest.StartTime(attemptRideStart))
+	analysis := rideanalysis.Analyze(parsed, nil, []official_climb.OfficialClimb{officialClimb}, official_climb.DefaultMatchPolicy())
+	aggregate := official_climb.AggregateAttempts(rideanalysis.Attempts(1, analysis, parsed))
+
+	profile := rideanalysis.MergeClimbProfile(officialClimb, []ride.Ride{parsed, shifted}, aggregate, official_climb.DefaultMatchPolicy(), climb.DefaultProfilePolicy())
+
+	assert.InDelta(t, 1000, profile.DistanceM, 0.01)
+	require.NotEmpty(t, profile.Sections)
+	assert.InDelta(t, 305, profile.Sections[0].StartElevationM, 1)
+	lastSection := profile.Sections[len(profile.Sections)-1]
+	assert.InDelta(t, 452, lastSection.EndElevationM, 2)
+	assert.InDelta(t, 1000, lastSection.EndDistanceM, 0.01)
+}
+
+func TestMergeClimbProfileRouteKeepsRecordedPoints(t *testing.T) {
+	parsed, officialClimb := attemptRideForClimb(t)
+	officialClimb.ID = 42
+	analysis := rideanalysis.Analyze(parsed, nil, []official_climb.OfficialClimb{officialClimb}, official_climb.DefaultMatchPolicy())
+	aggregate := official_climb.AggregateAttempts(rideanalysis.Attempts(1, analysis, parsed))
+
+	profile := rideanalysis.MergeClimbProfile(officialClimb, []ride.Ride{parsed}, aggregate, official_climb.DefaultMatchPolicy(), climb.DefaultProfilePolicy())
+
+	// Full recorded precision: every matched segment point is present, not a fixed resample.
+	require.Len(t, profile.Route, 2)
+	assert.InDelta(t, parsed.Coords[0].Lon, profile.Route[0].Lon, 1e-9)
+	assert.InDelta(t, parsed.Coords[0].Lat, profile.Route[0].Lat, 1e-9)
+	assert.InDelta(t, parsed.Coords[1].Lon, profile.Route[1].Lon, 1e-9)
+	assert.InDelta(t, parsed.Coords[1].Lat, profile.Route[1].Lat, 1e-9)
+}
+
+func TestMergeClimbProfileWithoutRides(t *testing.T) {
+	_, officialClimb := attemptRideForClimb(t)
+
+	profile := rideanalysis.MergeClimbProfile(officialClimb, nil, official_climb.Aggregate{DistanceM: 1000}, official_climb.DefaultMatchPolicy(), climb.DefaultProfilePolicy())
+
+	assert.Empty(t, profile.Sections)
+	assert.Nil(t, profile.Route)
+}