Closes#1948
Plugins receive debounced batches of files created, changed and removed outside the editor in open projects, as SDK `Event::FilesChanged` (delivered through `other("files-changed", …)`, so released WIT is unchanged), under the `events` capability and the plugin's path filters. Activation on these events requires API 1.3. Batches are coalesced per plugin through its actor, survive cancellation without losing deltas, and are dropped when the project or host shuts down.
Co-authored-by: arnaud-ritti <[email protected]>
Plugin API 1.2 gains an optional document-indexer export (plugin-indexing world). A plugin returns per document the keys it defines and refers to, aliases between key prefixes and gutter markers; the host indexes a trusted project in cancellable background batches, keeps the project-wide graph, and answers Go to Declaration / Ctrl-click and multi-target gutter markers from memory without calling the plugin again. Edits and file changes invalidate the affected entries; reload, disable or a failing runtime drops the plugin's graph.
The interface is limited to cross-file associations: icons chosen by file content and embedded-language regions are separate concerns for later interfaces. The plugin navigation choosers' titles are translated.
Co-authored-by: qjlqyf <[email protected]>