get-var is removed completely since its not needed at all

common/proto/table_script.proto

@@ -67,12 +67,10 @@ message PostTableScriptRequest {
   // Referencing data:
   //   - Structured table/column access (enforces link constraints):
   //       (steel_get_column "table_name" "column_name")
-  //       • self-references are allowed without links
+  //       • current-table references are read directly from the active row
   //       • other tables require an explicit link from the source table
   //         (table_definition_links) or the request fails
   //   - Raw SQL access is not supported; steel_query_sql is rejected
-  //   - Self variable access in transformed scripts:
-  //       (get-var "column_name") is treated as referencing the current table
   //
   // Math operations:
   //   - The script is transformed by steel_decimal; supported math forms include:
@@ -82,7 +80,7 @@ message PostTableScriptRequest {
   //     BIGINT, TEXT, BOOLEAN, DATE, TIMESTAMPTZ
   //
   // Dependency tracking and cycles:
-  //   - Dependencies are extracted from steel_get_column and get-var and stored
+  //   - Dependencies are extracted from steel_get_column calls and stored
   //     in script_dependencies with context
   //   - Cycles across tables are rejected (self-dependency is allowed)
   string script = 3;