* Migrate packages/flutter_tools/test/commands.shard/hermetic, part 1/3

* Fix tests

* Fix analysis

* Fix analyze_test

* Make AnalysisServer a local variable

* Chris's comments

This reverts commit 3802eb62.

This reverts commit 5fd259be.

This reverts commit 53d8cba3.

This reverts commit 8b6baae4.

Our current top crasher is an unclear error when ProcessManager fails to resolve an executable path. To fix this, we'd like to being adjusting the process resolution logic and adding more instrumentation to track failures. In order to begin the process, the ProcessManager has been folded back into the flutter tool

* opt out the flutter tool

* oops EOF

* fix import

* Update tool_backend.dart

* Update daemon_client.dart

* fix more

Split from #66776

Even if pub does not change the packge_config contents, it will still update a timestamp in one of the fields. This causes unnecessary rebuilds. To fix this, generate an additional file when running pub get that only contains the relevant fields and then update the KernelSnapshot rule to depend on it only.

[flutter_tools] use flutter tool handler for dwds resources and precache tool pub dependencies (#65814)

If the tool is downloaded from a precompiled snapshot, or if the backing source files in the pub cache are deleted, the dwds debugging functionality will break as the client.js file cannot be located. Instead use the PackageConfig to verify that package location, downloading if it is missing.

Override the dwds middleware to avoid Isolate.resolvePackageUri

Fixes #53644
Fixes #65475

Allow configuring the flutter_manifest to support a synthetic package, this is done through flutter: generate: true.

When running pub get, insert a flutter_gen entry into the packages if it does not already exist. This points to .dart_tool/flutter_gen, which can be updated to contain the generated intl sources (But doesn't currently)

Adds an integration test that verifies this code can be run and imported when enabled.

Part of #60914

flutter analyze was unconditionally using the cached dart-sdk for analysis, and was not running with the built SDK during local engine. This broke when trying to update the analyzer for null safety, since it required us to wait for the dart change to roll into the framework first.

This reverts commit 9ed3e5be.

flutter analyze was unconditionally using the cached dart-sdk for analysis, and was not running with the built SDK during local engine. This broke when trying to update the analyzer for null safety, since it required us to wait for the dart change to roll into the framework first.