Move source editor out of module (#12457)

* Update Copybara options in preparation for open-sourcing the source editor

* Move files

* Update paths

* Remove source-editor module and checks for its existence

* Explicitly mention CM6 license in files that contain code adapted from CM6

GitOrigin-RevId: 89b7cc2b409db01ad103198ccbd1b126ab56349b

services/web/frontend/js/features/source-editor/utils/tree-query.ts

@@ -0,0 +1,48 @@
+export { getNestingLevel, nestOutline } from './tree-operations/outline'
+
+export type {
+  FlatOutline,
+  FlatOutlineItem,
+  Outline,
+} from './tree-operations/outline'
+
+export {
+  iterateDescendantsOf,
+  previousSiblingIs,
+  nextSiblingIs,
+  isUnknownCommandWithName,
+} from './tree-operations/common'
+
+export {
+  cursorIsAtBeginEnvironment,
+  cursorIsAtEndEnvironment,
+  getEnvironmentArguments,
+} from './tree-operations/environments'
+
+export {
+  getAncestorStack,
+  ancestorNodeOfType,
+  ancestorOfNodeWithType,
+  getBibkeyArgumentNode,
+  descendantsOfNodeWithType,
+  matchingAncestor,
+} from './tree-operations/ancestors'
+
+export {
+  NormalTextSpan,
+  getNormalTextSpansFromLine,
+} from './tree-operations/text'
+
+export {
+  ifInType,
+  isInEmptyArgumentNodeForAutocomplete,
+} from './tree-operations/completions'
+
+export { tokenNames, Tokens } from './tree-operations/tokens'
+
+export {
+  commentIsOpenFold,
+  commentIsCloseFold,
+  findClosingFoldComment,
+  getFoldRange,
+} from './tree-operations/comments'