fix(tb): fix Vivado 2019.2 compatibility and add run_tb.sh

- Replace -include_dirs . with -i . (Vivado 2019.2 syntax)
- Add --timescale 1ns/1ps to all xelab commands
- Add LD_PRELOAD comment for ncurses compatibility
- Add run_tb.sh convenience script
  Usage: ./run_tb.sh mod_add
         ./run_tb.sh --list
- Update spec with Vivado 2019.2 compatibility notes

sync_rtl/sha3/TB/xsim_run.tcl

@@ -1,3 +1,7 @@
+# NOTE: On some systems, you may need:
+#   export LD_PRELOAD=/usr/lib64/libtinfo.so.5
+# before running this script.
+
 # xsim_run.tcl - Vivado xsim compilation and simulation script
 #
 # Compiles all SHA3 RTL sources plus testbenches and runs simulation.
@@ -62,13 +66,13 @@ xvlog -sv ${TB_DIR}/tb_sha3_xsim.v
 puts "=== Elaborating snapshots ==="
 
 # Simple sha3_top testbench (G mode, hardcoded vector)
-xelab tb_sha3_xsim_simple -s sha3_simple_sim
+xelab tb_sha3_xsim_simple -s sha3_simple_sim --timescale 1ns/1ps
 
 # Keccak core testbench (all-zero input)
-xelab tb_keccak_core_xsim -s keccak_core_sim
+xelab tb_keccak_core_xsim -s keccak_core_sim --timescale 1ns/1ps
 
 # File-based sha3_top testbench (reads vectors/g_basic_input.hex)
-xelab tb_sha3_xsim -s tb_sha3_xsim
+xelab tb_sha3_xsim -s tb_sha3_xsim --timescale 1ns/1ps
 
 # ================================================================
 # Step 4: Run simulations