add dotenvy for .env file loading

Loads .env and .env.{dev,test} in non-prod environments via runtime.exs.
Set OPENCLAW_GATEWAY_URL and OPENCLAW_GATEWAY_TOKEN in .env.

Author: clawd-conroy

config/runtime.exs

@@ -1,5 +1,10 @@
 import Config
 
+# Load .env file if present (dev/test convenience, ignored in prod releases)
+if config_env() != :prod do
+  Dotenvy.source([".env", ".env.#{config_env()}"])
+end
+
 # config/runtime.exs is executed for all environments, including
 # during releases. It is executed after compilation and before the
 # system starts, so it is typically used to load production configuration

mix.exs

@@ -85,6 +85,7 @@ defmodule ReifyStudio.MixProject do
       {:dns_cluster, "~> 0.2.0"},
       {:bandit, "~> 1.5"},
       {:fresh, "~> 0.4"},
+      {:dotenvy, "~> 0.8"},
       # Dev/test tools
       {:credo, "~> 1.7", only: [:dev, :test], runtime: false},
       {:credo_naming, "~> 2.1", only: [:dev, :test], runtime: false},

mix.lock

@@ -16,6 +16,7 @@
   "decimal": {:hex, :decimal, "2.3.0", "3ad6255aa77b4a3c4f818171b12d237500e63525c2fd056699967a3e7ea20f62", [:mix], [], "hexpm", "a4d66355cb29cb47c3cf30e71329e58361cfcb37c34235ef3bf1d7bf3773aeac"},
   "dialyxir": {:hex, :dialyxir, "1.4.7", "dda948fcee52962e4b6c5b4b16b2d8fa7d50d8645bbae8b8685c3f9ecb7f5f4d", [:mix], [{:erlex, ">= 0.2.8", [hex: :erlex, repo: "hexpm", optional: false]}], "hexpm", "b34527202e6eb8cee198efec110996c25c5898f43a4094df157f8d28f27d9efe"},
   "dns_cluster": {:hex, :dns_cluster, "0.2.0", "aa8eb46e3bd0326bd67b84790c561733b25c5ba2fe3c7e36f28e88f384ebcb33", [:mix], [], "hexpm", "ba6f1893411c69c01b9e8e8f772062535a4cf70f3f35bcc964a324078d8c8240"},
+  "dotenvy": {:hex, :dotenvy, "0.9.0", "aad823209cd7c13babe2dc310d9e54ce0203674cbd7631b0ced2a771e3a49532", [:mix], [], "hexpm", "ab959208a9ad02ff26ce1c5d4911668925c12a6cf58287ef77ae63161909c73b"},
   "ecto": {:hex, :ecto, "3.13.5", "9d4a69700183f33bf97208294768e561f5c7f1ecf417e0fa1006e4a91713a834", [:mix], [{:decimal, "~> 2.0", [hex: :decimal, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "df9efebf70cf94142739ba357499661ef5dbb559ef902b68ea1f3c1fabce36de"},
   "ecto_sql": {:hex, :ecto_sql, "3.13.4", "b6e9d07557ddba62508a9ce4a484989a5bb5e9a048ae0e695f6d93f095c25d60", [:mix], [{:db_connection, "~> 2.4.1 or ~> 2.5", [hex: :db_connection, repo: "hexpm", optional: false]}, {:ecto, "~> 3.13.0", [hex: :ecto, repo: "hexpm", optional: false]}, {:myxql, "~> 0.7", [hex: :myxql, repo: "hexpm", optional: true]}, {:postgrex, "~> 0.19 or ~> 1.0", [hex: :postgrex, repo: "hexpm", optional: true]}, {:tds, "~> 2.1.1 or ~> 2.2", [hex: :tds, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4.0 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "2b38cf0749ca4d1c5a8bcbff79bbe15446861ca12a61f9fba604486cb6b62a14"},
   "elixir_make": {:hex, :elixir_make, "0.9.0", "6484b3cd8c0cee58f09f05ecaf1a140a8c97670671a6a0e7ab4dc326c3109726", [:mix], [], "hexpm", "db23d4fd8b757462ad02f8aa73431a426fe6671c80b200d9710caf3d1dd0ffdb"},