feature: restore plugins by default

[sigasigasiga]

Did you check the docs?

• I have read all the lazy.nvim docs

Is your feature request related to a problem? Please describe.

As nearly all of us, I store my dotfiles in a git repo. lock-file.json is stored under version control too.
However, if I clone my setup to a new machine, open up neovim, Lazy begins to install the latest version of each plugin automatically and overwrites the lockfile.

To get the locked versions after that I need:

1. git restore path/to/lockfile
2. nvim -> :Lazy restore

which is quite inconvenient

Describe the solution you'd like

If lockfile exists then restore all the plugins, otherwise install the newest version.
If a plugin is listed in the spec but is not in the lockfile, then install the latest version and update the lockfile

Describe alternatives you've considered

1. git restore path/to/lockfile
2. nvim -> :Lazy restore

Additional context

No response

[stoicon]

#1804
(How to use the Lock file when lazy.nvim loads for the first time?)