CLI: expand config set with SecretRef/provider builders and dry-run (#49296)

* CLI: expand config set ref/provider builder and dry-run

* Docs: revert README Discord token example

src/cli/config-set-parser.ts

@@ -0,0 +1,43 @@
+export type ConfigSetMode = "value" | "json" | "ref_builder" | "provider_builder" | "batch";
+
+export type ConfigSetModeResolution =
+  | {
+      ok: true;
+      mode: ConfigSetMode;
+    }
+  | {
+      ok: false;
+      error: string;
+    };
+
+export function resolveConfigSetMode(params: {
+  hasBatchMode: boolean;
+  hasRefBuilderOptions: boolean;
+  hasProviderBuilderOptions: boolean;
+  strictJson: boolean;
+}): ConfigSetModeResolution {
+  if (params.hasBatchMode) {
+    if (params.hasRefBuilderOptions || params.hasProviderBuilderOptions) {
+      return {
+        ok: false,
+        error:
+          "batch mode (--batch-json/--batch-file) cannot be combined with ref builder (--ref-*) or provider builder (--provider-*) flags.",
+      };
+    }
+    return { ok: true, mode: "batch" };
+  }
+  if (params.hasRefBuilderOptions && params.hasProviderBuilderOptions) {
+    return {
+      ok: false,
+      error:
+        "choose exactly one mode: ref builder (--ref-provider/--ref-source/--ref-id) or provider builder (--provider-*), not both.",
+    };
+  }
+  if (params.hasRefBuilderOptions) {
+    return { ok: true, mode: "ref_builder" };
+  }
+  if (params.hasProviderBuilderOptions) {
+    return { ok: true, mode: "provider_builder" };
+  }
+  return { ok: true, mode: params.strictJson ? "json" : "value" };
+}