Add note about keychain

desktop/src/main/services/dir.ts

@@ -72,7 +72,6 @@ export const openLogDirectory = () => openDirectory(logDirectoryPath());
  * - macOS: ~/Library/Logs/Electron/ente.log    (dev)
  *
  * https://www.electronjs.org/docs/latest/api/app
- *
  */
 const logDirectoryPath = () => app.getPath("logs");
 

desktop/src/main/services/store.ts

@@ -14,6 +14,15 @@ export const clearStores = () => {
     watchStore.clear();
 };
 
+/**
+ * [Note: Safe storage keys]
+ *
+ * On macOS, `safeStorage` stores our data under a Keychain entry named
+ * "<app-name> Safe Storage". Which resolves to:
+ *
+ * - Electron Safe Storage (dev)
+ * - ente Safe Storage    (prod)
+ */
 export const saveEncryptionKey = (encryptionKey: string) => {
     const encryptedKey = safeStorage.encryptString(encryptionKey);
     const b64EncryptedKey = Buffer.from(encryptedKey).toString("base64");