feat(lsp): resolve symbols across workspace files

Assisted-by: GLM 5.3 Flash

docs/ARCHITECTURE.md

@@ -246,7 +246,11 @@ document store, republishes diagnostics on every change, and provides:
   pseudo-registers, labels, immediates, comments, directives, textflag macros);
 - **navigation**: go-to-definition from a label reference to its definition,
   find references, document highlights of every use of the symbol under the
-  cursor, rename, and workspace symbol search over the open documents;
+  cursor, rename, and workspace symbol search over the open documents and
+  the indexed workspace files: the `.s` files under the workspace root that
+  the editor has never opened, where an open buffer shadows its disk copy
+  and watched-file events plus a per-query freshness check keep the index
+  current;
 - **assists**: document formatting through the `format` package, inlay hints
   (the frame size after the TEXT argument area), signature help (the callee's
   `// func` signature while the cursor is on a `CALL`), and code actions

docs/CLI.md

@@ -455,7 +455,10 @@ semantic tokens, go-to-definition, find references, rename, document
 formatting, inlay hints, code actions, signature help, document highlights,
 workspace symbol search, #include document links, and folding ranges for
 function bodies. Definition, references and rename work across every open
-document.
+document and the wider workspace on disk: the server indexes the `.s` files
+under the workspace root that the editor has never opened, an open buffer
+always shadows its disk copy, and watched-file events together with a
+per-query freshness check keep the index current.
 
 ## version