Add DTD version of sidebar (#7919)
* Add DTD version of sidebar
* Review tweaks: backticks in docs, switch expression event, reorder getters+fields
* Include more information about registration/unregistration in EditorClient.editorServiceChanged
See https://github.com/flutter/devtools/pull/7919#discussion_r1676184914
* Replace some raw strings with constants
See https://github.com/flutter/devtools/pull/7919#discussion_r1676185640
* Split analytics IDs for legacy + DTD sidebars
See https://github.com/flutter/devtools/pull/7919#discussion_r1676190837
* Replace strings with constants, trailing commas, timeout TODO, doc improvements, remove experiment flag, unused PerformanceController
* Fix some casts + typo in GetDebugSessions call
* Switch SingleChildScrollViews to ListView.builders() and add some padding between buttons
* Add ListQueueValueNotifier and switch to it for the logging view of the simulated editor
See https://github.com/flutter/devtools/pull/7919#discussion_r1676278181
* Rename many "FakeEditor" and "EditorServer" classes to be "SimulatedEditor"s
* Use AutoDisposeControllerMixin for EditorClient implementations
See https://github.com/flutter/devtools/pull/7919#discussion_r1676178285
* Minor review tweaks
* Move ListQueueValueNotifier out of shared + add TODO for tests
* Update devtools_app to DTD 2.3
* Handle nullable deviceId for selectDevice to match the event
* Remove editor service spec
This is going in the SDK at https://dart-review.googlesource.com/c/sdk/+/375080
