feat(DuoChat): support project dependencies context item type

mentioned in commit 8de1a08d

mentioned in merge request gitlab-org/frontend/playground/accessibility-scanner!55 (closed)

mentioned in merge request gitlab-org/frontend/pajamas-adoption-scanner!352 (merged)

mentioned in merge request status-page!903

mentioned in commit e08f293c

mentioned in merge request gitlab-org/gitlab-services/design.gitlab.com!4168 (merged)

mentioned in merge request gitlab!172328 (closed)

mentioned in merge request gitlab-org/editor-extensions/gitlab-jetbrains-plugin!1249 (closed)

mentioned in commit b86e5d05

mentioned in merge request gitlab-org/frontend/playground/accessibility-scanner!58 (merged)