feat: Merge build-env into wrangler vars (wrangler config takes precedence)

build-env values are now added to the wrangler config vars section
so they are available at runtime. Values defined in the wrangler
environment file take precedence over build-env values.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: etchalon

action.yml

@@ -265,7 +265,7 @@ runs:
         echo "Merging $ENV_FILE into $NITRO_CONFIG..."
 
         # Pass file paths via environment variables to avoid escaping issues
-        NITRO_CONFIG="$NITRO_CONFIG" ENV_FILE="$ENV_FILE" node --eval '
+        NITRO_CONFIG="$NITRO_CONFIG" ENV_FILE="$ENV_FILE" BUILD_ENV='${{ inputs.build-env }}' node --eval '
         const fs = require("fs");
 
         // Strip JSONC comments (handles strings correctly to not break URLs)
@@ -350,13 +350,20 @@ runs:
 
         const nitroConfigPath = process.env.NITRO_CONFIG;
         const envFilePath = process.env.ENV_FILE;
+        const buildEnvJson = process.env.BUILD_ENV || "{}";
 
         // Read Nuxt-generated config (has main, assets, etc.)
         const nitroConfig = JSON.parse(fs.readFileSync(nitroConfigPath, "utf8"));
 
         // Read and parse environment config (has bindings, vars, etc.)
         const envConfig = JSON.parse(stripJsonComments(fs.readFileSync(envFilePath, "utf8")));
 
+        // Parse build-env and add as base vars (wrangler env vars take precedence)
+        const buildEnv = JSON.parse(buildEnvJson);
+        if (Object.keys(buildEnv).length > 0) {
+          envConfig.vars = { ...buildEnv, ...(envConfig.vars || {}) };
+        }
+
         // Merge: Nitro config + environment overrides
         const merged = deepMerge(nitroConfig, envConfig);