feat(webui): add tiers to picodata http-server

1. http-server:

    1. Get info about tiers from _pico_tier
    2. Get info about instance addresses from:
        - http: lua api
        - binary:  _pico_peer_addresses
    3. Switch from arrays to map where it makes sense
    4. Compose all the data to `cluster_state` object
    5. Get version information for lua api.

2. Tests:

    1. Add DeepDiff package to better diff for json
    2. Amend tests to new specification
    3. Get picodata version via lua api and use it in asserts

3. Chore:

    1. Add .envrc and .direnv to .gitingore (direnv specific files)
    2. Add .vscode to .gitignore.

Signed-off-by: Anatoly Popov <a.popov@picodata.io>