Extend /surveys endpoint to include waterlevel_value * Change SQL to use the same strategy as used in schema/gemma.sql for bottlenecks_geoserver to determine the waterlevel_value. * Extend go controler to deal with the situation where the value is not there. This is still suboptimal as this creates a json object for the NullInt64 value.

# documentation
**/README*
**/docs
**/*.md

# backend binary
cmd/gemma/gemma

# Dependency directories
**/node_modules

# local dotenv environment variables file
client/.env.local

# Tags tables
**/TAGS