chore(docs): Add dedicated page explaining how to manage FWF PATs

[ThorstenHans]

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[github-actions]

🚀 preview deployed successfully to Fermyon Cloud and available at https://fermyon-developer-pr-1582-kcss6hup.fermyon.app

[macolso]

Thank you for putting this together! I left a few small suggestions.

[macolso]

A few sentence-clarity tweaks

Suggested change

	To generate a new PAT, use the `spin aka auth token create` command. At least, you have to specify a name for your PAT. Without further ado, the PAT will expire after `30` days. You can customize the expiration using the `--expiration-days` (or `-e`) option. Also, an optional description could be provided using `--description` (or `-d`):
	To generate a new PAT, use the `spin aka auth token create` command. You must specify a name for your PAT. By default, the PAT will expire after `30` days. You can customize the expiration using the `--expiration-days` (or `-e`) option. Also, an optional description could be provided using `--description` (or `-d`):

[macolso]

Nit, may want to include this comment before the command.

[macolso]

Would it be helpful to include one other fictional PAT to illustrate the list functionality?

[macolso]

Sentence clarity changes and providing a "workaround" for readers who want to adjust experation period.

Suggested change

	Expiration in days can't be overwritten when regenerating a PAT. Instead, the value specified when creating the PAT will be used.
	When regenerating a PAT, you cannot change the expiration period. The regenerated token will use the same expiration settings as the original token. To change expiration period, you must delete the PAT and create a new one.