feat(lsp): interface dispatch in call hierarchy (0.11)

Index interface methods and extend Type for Trait relations so call
hierarchy can show implementors as outgoing targets and .Method call
sites as incoming.

- interface I { func M } + extend T for I tracking
- prepare/outgoing/incoming with data Iface#Method
- smoke_lsp_iface_hierarchy (Drawable.Draw ↔ Circle / Render)

tools/smoke_lsp_call_hierarchy.sh

@@ -57,7 +57,7 @@ if ! grep -q 'callHierarchyProvider' "$TMP/out.txt"; then
   cat "$TMP/out.txt"
   exit 1
 fi
-if ! grep -qE '0\.[89]\.0' "$TMP/out.txt"; then
+if ! grep -qE '0\.(8|9|10|11)\.0' "$TMP/out.txt"; then
   echo "WARN: unexpected bux-lsp version"
 fi