CLI: streamline startup paths and env parsing

Add shared parseBooleanValue()/isTruthyEnvValue() and apply across CLI, gateway, memory, and live-test flags for consistent env handling.
Introduce route-first fast paths, lazy subcommand registration, and deferred plugin loading to reduce CLI startup overhead.
Centralize config validation via ensureConfigReady() and add config caching/deferred shell env fallback for fewer IO passes.
Harden logger initialization/imports and add focused tests for argv, boolean parsing, frontmatter, and CLI subcommands.

src/utils/boolean.test.ts

@@ -0,0 +1,42 @@
+import { describe, expect, it } from "vitest";
+
+import { parseBooleanValue } from "./boolean.js";
+
+describe("parseBooleanValue", () => {
+  it("handles boolean inputs", () => {
+    expect(parseBooleanValue(true)).toBe(true);
+    expect(parseBooleanValue(false)).toBe(false);
+  });
+
+  it("parses default truthy/falsy strings", () => {
+    expect(parseBooleanValue("true")).toBe(true);
+    expect(parseBooleanValue("1")).toBe(true);
+    expect(parseBooleanValue("yes")).toBe(true);
+    expect(parseBooleanValue("on")).toBe(true);
+    expect(parseBooleanValue("false")).toBe(false);
+    expect(parseBooleanValue("0")).toBe(false);
+    expect(parseBooleanValue("no")).toBe(false);
+    expect(parseBooleanValue("off")).toBe(false);
+  });
+
+  it("respects custom truthy/falsy lists", () => {
+    expect(
+      parseBooleanValue("on", {
+        truthy: ["true"],
+        falsy: ["false"],
+      }),
+    ).toBeUndefined();
+    expect(
+      parseBooleanValue("yes", {
+        truthy: ["yes"],
+        falsy: ["no"],
+      }),
+    ).toBe(true);
+  });
+
+  it("returns undefined for unsupported values", () => {
+    expect(parseBooleanValue("")).toBeUndefined();
+    expect(parseBooleanValue("maybe")).toBeUndefined();
+    expect(parseBooleanValue(1)).toBeUndefined();
+  });
+});