fix: update aes-block metric thresholds for hierarchical synth

Update rules-base.json via bazelisk run aes_cipher_top_update.
Restore synth__design__instance__area__stdcell check now that
stat -hierarchy is used. Hierarchical block has no clock, so
timing thresholds are all 0.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>

Author: oharboe

flow/designs/asap7/aes-block/rules-base.json

@@ -1,4 +1,8 @@
 {
+    "synth__design__instance__area__stdcell": {
+        "value": 2010.0,
+        "compare": "<="
+    },
     "constraints__clocks__count": {
         "value": 0,
         "compare": "=="