add pql subsystem — daemon-side client + IPC handlers

PqlClient wraps pql CLI per D-003 (shell-out, never duplicate).
IPC verbs: pql.files, pql.meta, pql.backlinks, pql.outlinks,
pql.tags, pql.schema, pql.query, pql.doctor, pql.decisions.*,
pql.tickets.*, pql.plan.status. 15 new core tests.

Co-Authored-By: Claude <noreply@anthropic.com>

bin/clide.dart

@@ -20,8 +20,10 @@ import 'package:clide/src/daemon/editor_commands.dart';
 import 'package:clide/src/daemon/files_commands.dart';
 import 'package:clide/src/daemon/git_commands.dart';
 import 'package:clide/src/daemon/pane_commands.dart';
+import 'package:clide/src/daemon/pql_commands.dart';
 import 'package:clide/src/editor/registry.dart' show EditorRegistry;
 import 'package:clide/src/panes/registry.dart';
+import 'package:clide/src/pql/client.dart';
 
 Future<void> main(List<String> argv) async {
   if (argv.isEmpty) {
@@ -152,6 +154,9 @@ Future<void> _runDaemon(List<String> args) async {
 
   registerGitCommands(dispatcher, files.root, events);
 
+  final pql = PqlClient(workDir: files.root);
+  registerPqlCommands(dispatcher, pql);
+
   final stopping = Completer<void>();
   void shutdown(ProcessSignal sig) {
     if (!stopping.isCompleted) {