v0.7.6

• GPX trackpoints missing <time> no longer drag the segment's lap bounds to the epoch fallback.
• TCX no longer drops a lap's first trackpoint when StartTime postdates it.
• validateLapBoundaries() no longer skips corruption checks on activities with no GPS points.
• GeoJSON multi-Point activity_type is no longer locked to whichever feature parses first.
• GeoJSON no longer strands real data in additionalTracks when the first track feature is empty.
• IntegrityMode.silent no longer discards every diagnostic, only integrity ones.
• Raising maxPayloadBytes above 64MB no longer silently empties ActivityLoadResult.payload.
• merge() no longer skips normalize: true for a single-activity list.
• EncoderOptions is no longer a silent no-op for CSV/GeoJSON export; CSV lat/lon/elevation now default to fixed precision instead of raw toString() output.
• CSV no longer lets a custom channel named after a fixed column (elevation, latitude, etc.) corrupt the real field on round-trip.
• CSV now recognizes header variants like lat/lng/ele/hr, not just exact spellings.
• CSV now reports a duplicate header instead of letting the rightmost column win.
• splitBySport() no longer drops points in a gap between two laps of the same sport.
• Validation diagnostics no longer point callers at the nonexistent trimToPoints(); they suggest RawEditor.crop() instead.