feat(auth): allow to link connected apps to a user W-18394868

[cristiand391]

What does this PR do?

ref:

• feat: org login web support for multi auth W-18394868 salesforcecli/plugin-auth#1306
• feat: add linked connected apps for auth W-18394868 salesforcecli/plugin-agent#157

Doc: https://salesforce.quip.com/sUaFAknyDkue

This PR adds support for linking connected apps/ECAs to an authenticated user, allowing consumers to switch to a specific app for oauth-specific requirements like JWT-based access tokens, specific API scopes, etc.

Updates:

AuthInfo

Adds a new apps property that contains an object of CA/ECAs with oauth info needed for requests.
For the scope of this PR, the only supported way to add new apps is via the web server flow (see linked plugin-auth PR ⬆️ )

Connection:

Adds an app property to support picking up a linked app in the provided auth info:

  const authInfo = await AuthInfo.create({
    username: '[email protected]',
  });

  // get oauth creds from the main connected app in auth (opaque tokens)
  const conn = await Connection.create({
    authInfo,
  });

  // get oauth creds from the linked `agent-jwt-app`
  const jwtConn = await Connection.create({
    authInfo,
    app: 'agent-jwt-app',
  });

WebOAuthServer

Add support for linking apps to an authenticated users via the web server flow.
Before:
Web server only handled 1st time auth, always creating a new auth file
After
If you pass app and username params, after a successful auth in the browser it will save the oauth info in authinfo.apps[app].

What issues does this PR fix or reference?

@W-18394868@

[WillieRuemmele]

QA Notes

applies to three PRs

---

✅ : flag validation
✅ : invalid/unauth'd --username passed
✅ : invalid access token error message
✅ : refresh'd auth correctly
✅ : agent preview --app <incorrect app name> nice error message
✅ : multiple-app auth saves each separately
✅ : reauth with same app name error message

✅ : SFDX_AUTH_SCOPES="..." works to set scopes without flag
✅ : no interruption to normal command without new flags

[cristiand391]

the last retrieve NUTs failures are the concurrent api error, same NUTs were passing on previous commits.