feat(devkit): bump compatibility to Nx 19 - 21.x (#28243)

BREAKING CHANGE

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<!-- This is the behavior we have today -->

* `@nx/devkit` supports Nx 17 - 20.
* Node 18 - 22 is supported
* `ExecutorContext.projectGraph`, `ExecutorContext.nxJsonConfiguration`,
and `ExecutorContext.projectsConfigurations` is marked as optional
because `ExecutorContext` in some versions of Nx did not have them.
* `ExecutorContext.workspace` is marked as optional because
`ExecutorContext` in some versions of Nx did not have the above
properties which contain the same information.
* `ProjectGraphNode` is deprecated.
* `NxPluginV1.processProjectGraph` was deprecated long ago and there has
been a warning since.
* `appRootPath` has been deprecated for a long time.
* `parseTargetString` had a variant that did not take either the project
graph or the executor context.
* `readNxJson` has a variant which does not take a tree. This was not
clearly deprecated.
* There are handlers to require from `@nx/` instead of `@nrwl`
* Nx tries to get a root install from `@nrwl/cli`

<!-- This is the behavior we should expect with the changes in this PR
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* `@nx/devkit` supports Nx 19 - 21.
* Node 20 - 22 is supported
* `ExecutorContext.projectGraph`, `ExecutorContext.nxJsonConfiguration`,
and `ExecutorContext.projectsConfigurations` is marked as required
because `ExecutorContext` in Nx 19+ is guaranteed to have them.
* `ExecutorContext.workspace` is removed because the same information is
available in the above properties
* `ProjectGraphNode` is removed.
* `NxPluginV1` is no more. All plugins should be `NxPluginV2`.
* `workspaceRoot` is the replacement for `appRootPath`. `appRootPath` is
removed.
* `parseTargetString` no longer has a variant that did not take either
the project graph or the executor context.
* `readNxJson` still has a variant which does not take a tree but it's
clearly deprecated to be removed in Nx 21.
* `@nrwl` packages are no more so we don't have to redirect requires
anymore.
* `@nrwl/cli` is no more so Nx shouldn't try to get a root install there
*

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merged. -->

Fixes #

packages/devkit/package.json

@@ -38,7 +38,7 @@
     "minimatch": "9.0.3"
   },
   "peerDependencies": {
-    "nx": ">= 17 <= 20"
+    "nx": ">= 19 <= 21"
   },
   "publishConfig": {
     "access": "public"