Add development-scripts agent skill

Ports generic-scripts-module-v1 into a routed skill: module anatomy, shared
loggers/base modules, Taskfile integration, workflows, and pattern decisions.

Fixes a latent defect in the loggers example that silenced all logging in the
module scaffold: loggers/lib/--index-api.sh now sources --env-vars-reader.sh,
and the reader preserves already-exported values so caller overrides still win.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

assets/base/lib/-prompt-for-env-var.sh

@@ -0,0 +1,35 @@
+#!/bin/bash
+set -e
+# -------------------------------------------------------------------------------------
+# IBM Confidential
+# 6949-70F, 6949-80D
+# © Copyright IBM Corp. 2018, 2024
+# US Government Users Restricted Rights - Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp.
+# -------------------------------------------------------------------------------------
+
+prompt_for_env_var() {
+  local var_name="$1"
+  local function_name="${FUNCNAME[1]:-unknown_function}"
+
+  if [ -z "${!var_name}" ]; then
+    while true; do
+      _loggers_emptyLine
+      echo -e "Provide a value for ${var_name} environment variable!\n"
+      read -rep "> " tmp_value
+
+      if [ -n "${tmp_value}" ]; then
+        export "${var_name}=${tmp_value}"
+        export ENV_VAR_KEY="${var_name}"
+        export ENV_VAR_VALUE="${tmp_value}"
+        _base_localStorage_saveEnvVariable2_fileDotEnv
+        break
+      else
+        _loggers_emptyLine
+        _loggers_warn "${function_name}" "Provided value cannot be empty!"
+      fi
+    done
+  fi
+
+  _loggers_debug "${function_name}" "${var_name}: *REDACTED*"
+}
+