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/agents/skills/frontmatter.test.ts

@@ -0,0 +1,20 @@
+import { describe, expect, it } from "vitest";
+
+import { resolveSkillInvocationPolicy } from "./frontmatter.js";
+
+describe("resolveSkillInvocationPolicy", () => {
+  it("defaults to enabled behaviors", () => {
+    const policy = resolveSkillInvocationPolicy({});
+    expect(policy.userInvocable).toBe(true);
+    expect(policy.disableModelInvocation).toBe(false);
+  });
+
+  it("parses frontmatter boolean strings", () => {
+    const policy = resolveSkillInvocationPolicy({
+      "user-invocable": "no",
+      "disable-model-invocation": "yes",
+    });
+    expect(policy.userInvocable).toBe(false);
+    expect(policy.disableModelInvocation).toBe(true);
+  });
+});