feat(lsp): call hierarchy prepare / incoming / outgoing (0.8)

Expose LSP call hierarchy over a lightweight textual call graph of
known functions and Name( call sites across the workspace.

- prepareCallHierarchy on func decl or call site
- incomingCalls / outgoingCalls with fromRanges
- smoke_lsp_call_hierarchy + test-lsp wiring

tools/smoke_lsp_rename.sh

@@ -59,7 +59,7 @@ if ! grep -q 'renameProvider' "$TMP/out.txt"; then
   echo "FAIL: initialize missing renameProvider"
   exit 1
 fi
-if ! grep -qE '0\.[567]\.0' "$TMP/out.txt"; then
+if ! grep -qE '0\.[5678]\.0' "$TMP/out.txt"; then
   echo "WARN: unexpected bux-lsp version in initialize"
 fi