Packaging: Rafactor Javascript core libraries

Extract the external facing `qll` files into the codeql/javascript-all
query pack.

javascript/ql/lib/semmle/javascript/frameworks/Prettier.qll

@@ -0,0 +1,29 @@
+/**
+ * Provides classes and predicates for working with the [prettier](https://www.npmjs.com/package/prettier) library.
+ */
+
+import javascript
+
+/** Provides classes and predicates modelling aspects of the [prettier](https://www.npmjs.com/package/prettier) library. */
+private module Prettier {
+  /**
+   * A taint step from the [prettier API](https://prettier.io/docs/en/api.html).
+   */
+  private class PrettierTaintStep extends TaintTracking::SharedTaintStep {
+    override predicate step(DataFlow::Node pred, DataFlow::Node succ) {
+      exists(API::CallNode call |
+        call = API::moduleImport("prettier").getMember("format").getACall()
+      |
+        pred = call.getArgument(0) and
+        succ = call
+      )
+      or
+      exists(API::CallNode call |
+        call = API::moduleImport("prettier").getMember("formatWithCursor").getACall()
+      |
+        pred = call.getArgument(0) and
+        succ = call.getReturn().getMember("formatted").getAnImmediateUse()
+      )
+    }
+  }
+}