Faro should be able to persist and assume a session out of the box

[cedricziel]

Description

My current understanding is that Faro creates a new session whenever it is initialized.

My expectation for a real-user-monitoring library is that it would persist the session in the browser and assume it whenever a user resumes their actions within a reasonable time-frame.

This would:

• track a user session across browser tabs
• track a user session across a static web page, where every navigation means reloading all scripts

Proposed solution

• add session info to local-storage
• add information about timeout
• make timeout configurable

Prior art:

• Instana weasel
• New Relic Browser Agent

• [x] Persist current session in the browser
• [x] Faro should pick up a persisted session and resume it (session_resumed event?)

  
  ```[tasklist]
  ### Product outcomes

• [ ] In product instructions include an option to activate tracking of user sessions across page loads
• [ ] We communicate that this option can have DataPrivacy related impact
• [ ] We showcase in a blog post, how tracking over multiple page-loads is beneficial for a business
• [ ] User sessions have a maximum lifetime which can be enforced receiver-side

### Tasks

[LittleLadySunshine]

@cedricziel good, yeah?

[kpelelis]

@cedricziel is it okay if we either close this or merge it with the epic that we have for 23Q3

grafana/app-o11y#299

[cedricziel]

@kpelelis I have linked it to the epic

[codecapitano]

PoC PR got merged today.