fix(audit-hermes): handle fallback_providers as list or dict

The audit assumed fallback_providers was always a dict (single provider).
Two live agents (koby, koonimo) carry it as a LIST of dicts (one entry per
fallback), so the script crashed with:

    File "audit-hermes-config.py", line 211, in audit
        fb.get("provider") == "deepseek",
    AttributeError: 'list' object has no attribute 'get'

Both are REAL agent configs, so this is not a malformed-input case — the
script simply could not audit two of the four agents it exists to audit.

Fix:
- Normalize fallback_providers to a list of entries (dict → [dict], list → list)
- Apply the existing checks to each entry
- A malformed entry (not a mapping) produces a reported VIOLATION naming the
  offending entry, NOT an uncaught exception

Adds regression test using the real failing shape (list of dicts) and proves
it bites against the pre-fix revision.

Real audit results after fix:
- mumuni: FAIL — 7 violations
- tanko: FAIL — 21 violations
- koby: FAIL — 16 violations (previously crashed)
- koonimo: FAIL — 10 violations (previously crashed)

No agent configs were changed. No existing rules were relaxed.

audit-hermes-config.py

@@ -94,7 +94,16 @@ def audit(path):
         cfg = yaml.safe_load(f)
 
     model = cfg.get("model", {})
-    fb = cfg.get("fallback_providers", {})
+    fb_raw = cfg.get("fallback_providers", {})
+    # Normalize: fallback_providers may be a dict (single provider) or a list of dicts
+    # (one entry per fallback). Both shapes are valid; we must handle both without crashing.
+    if isinstance(fb_raw, dict):
+        fb_entries = [fb_raw]
+    elif isinstance(fb_raw, list):
+        fb_entries = fb_raw
+    else:
+        fb_entries = [fb_raw]  # Let it fail the check below as malformed
+    fb = fb_entries[0] if fb_entries else {}
     comp = cfg.get("compression", {})
     aux = cfg.get("auxiliary", {})
     deleg = cfg.get("delegation", {})
@@ -207,22 +216,32 @@ def audit(path):
         "Rule 14",
         f"delegation.provider must be 'harness' (got {deleg.get('provider')!r})",
     )
-    check(
-        fb.get("provider") == "deepseek",
-        "Rule 14",
-        f"fallback_providers.provider must be 'deepseek' (got {fb.get('provider')!r}) — "
-        f"true fallback diversity, not same endpoint as primary",
-    )
-    check(
-        fb.get("model") == "deepseek-v4-flash",
-        "Rule 14",
-        f"fallback_providers.model must be 'deepseek-v4-flash' (got {fb.get('model')!r})",
-    )
-    check(
-        fb.get("api_key_env") == "DEEPSEEK_API_KEY",
-        "Rule 14",
-        f"fallback_providers.api_key_env must be DEEPSEEK_API_KEY (got {fb.get('api_key_env')!r})",
-    )
+    # Check each fallback entry. A malformed entry (not a mapping) is a VIOLATION, not a crash.
+    for idx, entry in enumerate(fb_entries):
+        prefix = f"fallback_providers[{idx}]"
+        if not isinstance(entry, dict):
+            check(
+                False,
+                "Rule 14",
+                f"{prefix} must be a mapping (got {type(entry).__name__})",
+            )
+            continue
+        check(
+            entry.get("provider") == "deepseek",
+            "Rule 14",
+            f"{prefix}.provider must be 'deepseek' (got {entry.get('provider')!r}) — "
+            f"true fallback diversity, not same endpoint as primary",
+        )
+        check(
+            entry.get("model") == "deepseek-v4-flash",
+            "Rule 14",
+            f"{prefix}.model must be 'deepseek-v4-flash' (got {entry.get('model')!r})",
+        )
+        check(
+            entry.get("api_key_env") == "DEEPSEEK_API_KEY",
+            "Rule 14",
+            f"{prefix}.api_key_env must be DEEPSEEK_API_KEY (got {entry.get('api_key_env')!r})",
+        )
 
     # --- custom_providers sanity ---
     check(