Language servers never got workspace/didChangeWatchedFiles, so files changed on disk outside the editor (checkout, pull, another tool) stayed unknown to them; jdtls's incremental build skipped them and Java / Spring Boot launches ran their old classes (e.g. another module of a multi-module project). The project's file watcher now forwards each batch to the running servers: created, changed and removed files of a server's languages under its root.
Refs #1015