Add optional height1_ft/height2_ft to contact schema, submit form, and
edit form (direct + suggest-edit paths). Heights flow through to the
elevation-profile terrain analysis so clearance and diffraction are
computed from the actual antenna height instead of a 10-ft default.
Editing heights resets terrain_status and re-enqueues
TerrainProfileWorker so the stored path analysis picks up the new
geometry.
Also fix mark_likely_duct/3: the pattern was grabbing the element
instead of the index, so no duct ever got flagged as the likely
propagation path even when extract_ducts returned a valid layer.
