Investigate Artworks Reloading Every Time App Is Opened

### Description

User in #7373520-zen reports that, every time they open the app, the artworks need to reload. This happens even after only having the app closed for seconds.

Other notes:
- happens on WiFi and mobile data
- Background refresh: true
- Battery restriction: Unrestricted

### Step-by-step reproduction instructions

So far, we've been able to replicate the behavior, but only after the app has been inactive for quite some time. If the app is opened again in the next few minutes or so, there is no reloading going on.

We have even tested with a rather slow test device with a lot of subscriptions.

### Screenshots or screen recording

https://github.com/Automattic/pocket-casts-android/assets/74066241/f150a068-195a-46f4-bcaa-1ec69eb3dbf0

### Did you search for existing bug reports?

- [X] I have searched for existing bug reports.

### Device, Operating system, and Pocket Casts app version

App version : 7.51 (9160)
Phone: samsung - a53x - SM-A536E - a53x
Android version: 13 SDK 33

Start by reproducing the reload behavior on the reported Samsung A53 running Android 13, comparing reopening after seconds with reopening after a longer inactive period on WiFi and mobile data. Trace the artwork loading path and app lifecycle behavior; done means identifying why cached artworks reload and verifying that reopening the app no longer unnecessarily reloads them.

Written by the indexing model from the issue text.