chore: improve storage/ implementation; use log(...) consistently (#473)

This PR tidies up primitives under storage/.

**Noop changes:**

* Promote logger implementation to top-level utility outside of agent/
* Use logger within storage primitives
* Cleanup doc strings and comments

**Functional changes:**

* Increase command history size to 10_000
* Remove unnecessary debounce implementation and ensure a session ID is
created only once per agent loop

---------

Signed-off-by: Thibault Sottiaux <tibo@openai.com>

codex-cli/src/utils/config.ts

@@ -8,8 +8,8 @@
 
 import type { FullAutoErrorMode } from "./auto-approval-mode.js";
 
-import { log } from "./agent/log.js";
 import { AutoApprovalMode } from "./auto-approval-mode.js";
+import { log } from "./logger/log.js";
 import { providers } from "./providers.js";
 import { existsSync, mkdirSync, readFileSync, writeFileSync } from "fs";
 import { load as loadYaml, dump as dumpYaml } from "js-yaml";