Initial commit: rustytokens — native codebase indexer + MCP server

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

tests/fixtures/cdemo/dead.c

@@ -0,0 +1 @@
+int c_dead(void) { return 0; }

tests/fixtures/cdemo/main.c

@@ -0,0 +1,5 @@
+#include "util.h"
+
+int main(void) {
+    return helper();
+}

tests/fixtures/cdemo/util.c

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+#include "util.h"
+
+int helper(void) { return 0; }

tests/fixtures/cdemo/util.h

@@ -0,0 +1 @@
+int helper(void);