chore: document function config in toml (#2925)

pkg/config/templates/config.toml

@@ -236,8 +236,18 @@ enabled = true
 # Configure one of the supported request policies: `oneshot`, `per_worker`.
 # Use `oneshot` for hot reload, or `per_worker` for load testing.
 policy = "oneshot"
+# Port to attach the Chrome inspector for debugging edge functions.
 inspector_port = 8083
 
+# Use these configurations to customize your Edge Function.
+# [functions.MY_FUNCTION_NAME]
+# enabled = true
+# verify_jwt = true
+# import_map = "./functions/MY_FUNCTION_NAME/deno.json"
+# Uncomment to specify a custom file path to the entrypoint.
+# Supported file extensions are: .ts, .js, .mjs, .jsx, .tsx
+# entrypoint = "./functions/MY_FUNCTION_NAME/index.ts"
+
 [analytics]
 enabled = true
 port = 54327