libs : rename libcommon -> libllama-common (#21936)

* cmake : allow libcommon to be shared

* cmake : rename libcommon to libllama-common

* cont : set -fPIC for httplib

* cont : export all symbols

* cont : fix build_info exports

* libs : add libllama-common-base

* log : add common_log_get_verbosity_thold()

common/build-info.h

@@ -0,0 +1,11 @@
+#pragma once
+
+int llama_build_number(void);
+
+const char * llama_commit(void);
+const char * llama_compiler(void);
+
+const char * llama_build_target(void);
+const char * llama_build_info(void);
+
+void llama_print_build_info(void);