Adds the baseline quality-gate and test-support dependencies every svelixir project gets regardless of options, and pins the Elixir version floor to ~> 1.20. type=web projects additionally get sobelow -- Config already writes .sobelow-conf for type=web projects, and docker's own generated CI runs mix sobelow --config, so the dependency itself must exist too, not just its config file. project.otp.repo=true additionally gets uniq (UUIDv7 generation for OtpRepo's Schema convention, both project types); type=otp also gets ecto_sql/postgrex -- type=web already has both via mix phx.new.