fix: widen geo-prefix parity to all Bedrock ID normalization sites

The au./apac. additions from #46297 and #65973 covered
is_anthropic_bedrock_model and _normalize_bedrock_model_name; the same
prefix lists exist at two more sibling sites that would still miss
au./ca./sa./me./af. profiles:
- anthropic_adapter._looks_like_bedrock_model_id
- chat_completion_helpers (reasoning stale-timeout floor resolution)

All four sites now share the same 11-prefix set (global/us/eu/apac/ap/
au/jp/ca/sa/me/af, longest-first so apac. wins over ap.). The Bedrock
picker's BEDROCK_GEO_PREFIXES is deliberately untouched: au. absent
there fails open (profile shown), and adding it requires a region-to-geo
remap to avoid hiding Sydney profiles.

agent/anthropic_adapter.py

@@ -1582,7 +1582,10 @@ def _is_bedrock_model_id(model: str) -> bool:
     """
     lower = model.lower()
     # Regional inference-profile prefixes
-    if any(lower.startswith(p) for p in ("global.", "us.", "eu.", "ap.", "jp.")):
+    if any(lower.startswith(p) for p in (
+        "global.", "us.", "eu.", "apac.", "ap.", "au.", "jp.",
+        "ca.", "sa.", "me.", "af.",
+    )):
         return True
     # Bare Bedrock model IDs: provider.model-family
     if lower.startswith("anthropic."):

agent/bedrock_adapter.py

@@ -448,7 +448,10 @@ def is_anthropic_bedrock_model(model_id: str) -> bool:
     """
     model_lower = model_id.lower()
     # Strip regional prefix if present
-    for prefix in ("us.", "global.", "eu.", "apac.", "ap.", "au.", "jp."):
+    for prefix in (
+        "global.", "us.", "eu.", "apac.", "ap.", "au.", "jp.",
+        "ca.", "sa.", "me.", "af.",
+    ):
         if model_lower.startswith(prefix):
             model_lower = model_lower[len(prefix):]
             break

agent/chat_completion_helpers.py

@@ -341,7 +341,10 @@ def _bedrock_reasoning_stale_floor(model_id: object) -> "float | None":
     if not model_id or not isinstance(model_id, str):
         return None
     name = model_id.strip().lower()
-    for prefix in ("us.", "eu.", "apac.", "ap.", "global.", "jp."):
+    for prefix in (
+        "global.", "us.", "eu.", "apac.", "ap.", "au.", "jp.",
+        "ca.", "sa.", "me.", "af.",
+    ):
         if name.startswith(prefix):
             name = name[len(prefix):]
             break