feat(cli): improve offline support (#22961)

# Why

Offline support is sometimes needed in parts of other commands besides
`start`, this PR introduces an `EXPO_OFFLINE` env var which can be
gener

feat(cli): improve offline support (#22961)

# Why

Offline support is sometimes needed in parts of other commands besides
`start`, this PR introduces an `EXPO_OFFLINE` env var which can be
generally used to force offline support.
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Please describe the motivation for this PR, and link to relevant GitHub
issues, forums posts, or feature requests.
-->

# How

- `EXPO_OFFLINE`
- Show a better error message when your computer is connected to wifi
but there's no signal.
- Assert in `npx expo login` and `npx expo register` when `EXPO_OFFLINE`
is set.
- Fail better when validating versions offline.

In the case of running `npx expo` without wifi:

## Before

```
june-16 �� nexpo
Starting project at /Users/evanbacon/Documents/GitHub/lab/june-16
Starting Metro Bundler
Unable to reach Expo servers. Falling back to using the cached dependency map (bundledNativeModules.json) from the package "expo" installed in your project.
FetchError: request to https://api.expo.dev/v2/versions/latest failed, reason: getaddrinfo ENOTFOUND api.expo.dev
FetchError: request to https://api.expo.dev/v2/versions/latest failed, reason: getaddrinfo ENOTFOUND api.expo.dev
at ClientRequest.<anonymous> (/Users/evanbacon/Documents/GitHub/expo/node_modules/node-fetch/lib/index.js:1491:11)
at ClientRequest.emit (node:events:513:28)
at TLSSocket.socketErrorListener (node:_http_client:502:9)
at TLSSocket.emit (node:events:513:28)
at emitErrorNT (node:internal/streams/destroy:151:8)
at emitErrorCloseNT (node:internal/streams/destroy:116:3)
at process.processTicksAndRejections (node:internal/process/task_queues:82:21)
```

## After

```
june-16 �� nexpo
Starting project at /Users/evanbacon/Documents/GitHub/lab/june-16
Starting Metro Bundler
Unable to reach Expo servers. Falling back to using the cached dependency map (bundledNativeModules.json) from the package "expo" installed in your project.
CommandError: Network connection is unreliable. Try again with the environment variable `EXPO_OFFLINE=1` to skip network requests.
```


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How did you build this feature or fix this bug and why?
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# Test Plan

- Updated tests and added new tests for things like the register
command.

---------

Co-authored-by: Expo Bot <[email protected]>

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[cli][packages] unify the default dev server port to 8081 (#22880)

# Why

for historical reasons, when running `npx expo start` the dev-server listens to port 19000, and running `npx expo start --

[cli][packages] unify the default dev server port to 8081 (#22880)

# Why

for historical reasons, when running `npx expo start` the dev-server listens to port 19000, and running `npx expo start --dev-client` it listens to port 8081. since we are now on our effort to deprecate `--dev-client` option, it is better to unify the listening port.
close ENG-8936

# How

- update packages/**/*.ts for port 19000 -> 8081
- search more occurrences for 19000 to 8081

# Test Plan

- ci passed
- bare-expo
- unversioned expo go + ncl

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