* exclude xcworkspace that begins with a period

* fix if spacing, add comment

* add unit test for when no xcworkspace found

* update to use xcodeWorkspace, make it nullable and refactor

* check if hostAppRoot exists before trying to get xcworkspace

* use local variables to take advantage of type promotion

* only check if not null, don't need to check if exists

* readd exist check for migrate

* readd missing line at end of file

This reverts commit e1337218.

The code to generate platform files used to use the presence of an
'example' folder to determine whether or not a project was a plugin (in
which case that generation is bypassed). Later, robust detection was
added based on the pubspec.yaml `plugin` key, but the old check was left
in place. This creates false positives where people who add an example
folder to their app project start getting mysterious failures.

Since the pubspec check is definitive, there's no reason to continue to
use the presence of `example` as an indicator at all.

Fixes https://github.com/flutter/flutter/issues/87007

Revert "Reland "Exit on deprecated v1 embedding when trying to run or build (#92901)" (#93386)" (#93518)

This reverts commit eabb7cbc.

It broke multiple tests.

This reverts commit 6153bbef.

This reverts commit 9038fac9.

This reverts commit 058dfd49.

This adds avoid_dynamic_calls to the list of lints, and fixes all instances where it was violated.

Importantly, this lint is NOT turned on for flutter/packages/test, because those changes are happening in another PR: #84478