Zone coach

When the run gets hard, `Zone coach` keeps your head clear. It is a running Data Field that delivers short, punchy coaching lines you can read in a split second. Using heart-rate zones (Z1-Z5), slope trend (uphill/flat/downhill), and distance events (every 1 km + key markers), it gives timely cues without breaking your rhythm. The goal is simple: less overthinking, better pacing, stronger finish. Key features: 1. Heart-rate-zone guidance (Z1-Z5) 2. Slope-aware feedback (UP/FL/DN) 3. Distance event messages (every 1 km + major markers) 4. Multi-language support (JPN/ENG/SPA/FRE/DEU)