feat(infra): tracing recovery, browser cleanup, CLI fixes, UI workspace split (#709)

- Tracing: recover stale running traces/spans on startup (PG + SQLite)
- Browser: Chrome orphan cleanup via launcher PID, timeouts, Leakless
- Claude CLI: WaitDelay 5s + context-cancel early exit
- Agent loop: safety-net defer to finalize orphan root traces
- UI: split workspace sharing into separate Memory and KG toggles
- Minor: for-range idiom, min() builtin

internal/agent/loop_cancel_test.go

@@ -18,7 +18,7 @@ func TestParallelToolCollection_ContextCancel(t *testing.T) {
 	var err error
 
 collectLoop:
-	for i := 0; i < 3; i++ {
+	for range 3 {
 		select {
 		case r, ok := <-resultCh:
 			if !ok {
@@ -50,7 +50,7 @@ func TestParallelToolCollection_AllComplete(t *testing.T) {
 	collected := make([]indexedResult, 0, 3)
 
 collectLoop:
-	for i := 0; i < 3; i++ {
+	for range 3 {
 		select {
 		case r, ok := <-resultCh:
 			if !ok {