Onboarding improvements

[maninak]

Results:

🚀 Enhancements

• onboarding: multiple improvements on the getting-started flow:
  • better clarify required next steps on each Welcome Views
  • better clarify that the existing init button will perform git init (not rad init)
  • better inform and reassure the user about rad init when offering it to them
  • offer a link to the Radicle User Guide for further info
  • misc copy alignments between Welcome Views
• onboarding: multiple improvements on the cli-troubleshooting flow:
  • for the option with external link to install Radicle, it will now take the user directly to the "get-started" section of the Radicle website
  • suggest the modern ~/.radicle/bin/rad vs the legacy /usr/bin/rad as a path to the CLI binary in the placeholder of the input for a custom path to CLI
  • general copy improvements across all branches of the flow

🩹 Fixes

• onboarding: don't show simultaneously cli-troubleshooting and getting-started Welcome Views when the rad CLI isn't installed
• auth: use the term "seal" instead of "lock" in commands and logs, e.g. "unsealed identity" instead of "unlocked identity", which better aligns with the CLI terminology and communicates facts slightly more accurately

🚩 Known Issues

• missing Welcome Screen for the case when a git repo is initialized but has no commits yet (should have button redirecting to Source Control), which will always fail rad init
• missing button rad init and in existing Welcome Screen asking the user to run it in the terminal (requires #149)
• patches of private repos aren't listed
• detection of auth to change patch status with r-click and misc mutations isn't being automatically applied if a user activated the extension before having a local identity created.