feat(lsp): support Java class file contents and improve definition navigation handling

- Add `_lsp_java_class_file_contents` request to fetch contents of compiled Java classes via LSP (`java/classFileContents`).
- Handle `java/classFileContents` responses by opening a new buffer with Java syntax highlighting and inserting the returned source.
- Update definition handling to pass URI and range, enabling precise cursor placement after navigation.
- Detect `jdt://` URIs in `textDocument/definition` responses and request class file contents instead of direct navigation.
- Move goto navigation logic into `LSPServerEventsMixin`, using event system to access the active view and position the cursor.
- Expose `emit` and `emit_to` to the response cache for event dispatching.
- Restrict completion activation to `USER_REQUESTED`.
- Add TODO note about mapping language IDs to dedicated response handlers.

plugins/code/ui/lsp_manager/plugin.py

@@ -55,11 +55,9 @@ class Plugin(PluginCode):
         lsp_manager.load_lsp_servers_config()
         lsp_manager.set_source_view(source_view)
         lsp_manager.load_lsp_servers_config_placeholders()
-        lsp_manager.provider.response_cache._prompt_completion_request = \
-            self._prompt_completion_request
-
-        lsp_manager.provider.response_cache._prompt_goto_request = \
-            self._prompt_goto_request
+        lsp_manager.provider.response_cache.emit = self.emit
+        lsp_manager.provider.response_cache.emit_to = self.emit_to
+        lsp_manager.provider.response_cache._prompt_completion_request = self._prompt_completion_request
 
     def run(self):
         ...
@@ -82,15 +80,6 @@ class Plugin(PluginCode):
         self.emit_to("completion", event)
 
 
-    def _prompt_goto_request(self, uri: str):
-        event  = Event_Factory.create_event(
-            "get_active_view",
-        )
-        self.emit_to("source_views", event)
-        view = event.response
-        view._on_uri_data_received( [uri] )
-
-
 class Handler:
     @staticmethod
     def execute(