feat: add pre-prompt context size diagnostic logging (openclaw#8930) thanks @Glucksberg

Verified:
- pnpm build
- pnpm check
- pnpm test

Co-authored-by: Glucksberg <80581902+Glucksberg@users.noreply.github.com>
Co-authored-by: Tak Hoffman <781889+Takhoffman@users.noreply.github.com>

src/logging/subsystem.test.ts

@@ -0,0 +1,56 @@
+import { afterEach, describe, expect, it } from "vitest";
+import { setConsoleSubsystemFilter } from "./console.js";
+import { resetLogger, setLoggerOverride } from "./logger.js";
+import { createSubsystemLogger } from "./subsystem.js";
+
+afterEach(() => {
+  setConsoleSubsystemFilter(null);
+  setLoggerOverride(null);
+  resetLogger();
+});
+
+describe("createSubsystemLogger().isEnabled", () => {
+  it("returns true for any/file when only file logging would emit", () => {
+    setLoggerOverride({ level: "debug", consoleLevel: "silent" });
+    const log = createSubsystemLogger("agent/embedded");
+
+    expect(log.isEnabled("debug")).toBe(true);
+    expect(log.isEnabled("debug", "file")).toBe(true);
+    expect(log.isEnabled("debug", "console")).toBe(false);
+  });
+
+  it("returns true for any/console when only console logging would emit", () => {
+    setLoggerOverride({ level: "silent", consoleLevel: "debug" });
+    const log = createSubsystemLogger("agent/embedded");
+
+    expect(log.isEnabled("debug")).toBe(true);
+    expect(log.isEnabled("debug", "console")).toBe(true);
+    expect(log.isEnabled("debug", "file")).toBe(false);
+  });
+
+  it("returns false when neither console nor file logging would emit", () => {
+    setLoggerOverride({ level: "silent", consoleLevel: "silent" });
+    const log = createSubsystemLogger("agent/embedded");
+
+    expect(log.isEnabled("debug")).toBe(false);
+    expect(log.isEnabled("debug", "console")).toBe(false);
+    expect(log.isEnabled("debug", "file")).toBe(false);
+  });
+
+  it("honors console subsystem filters for console target", () => {
+    setLoggerOverride({ level: "silent", consoleLevel: "info" });
+    setConsoleSubsystemFilter(["gateway"]);
+    const log = createSubsystemLogger("agent/embedded");
+
+    expect(log.isEnabled("info", "console")).toBe(false);
+  });
+
+  it("does not apply console subsystem filters to file target", () => {
+    setLoggerOverride({ level: "info", consoleLevel: "silent" });
+    setConsoleSubsystemFilter(["gateway"]);
+    const log = createSubsystemLogger("agent/embedded");
+
+    expect(log.isEnabled("info", "file")).toBe(true);
+    expect(log.isEnabled("info")).toBe(true);
+  });
+});