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/components/chat/terminal-chat-input-thinking.tsx

@@ -1,4 +1,4 @@
-import { log } from "../../utils/agent/log.js";
+import { log } from "../../utils/logger/log.js";
 import { Box, Text, useInput, useStdin } from "ink";
 import React, { useState } from "react";
 import { useInterval } from "use-interval";