fix(providers): report why a lazy SDK install did not land

_get_anthropic_sdk() swallowed every ensure_import("anthropic") failure and
_require_sdk() then told the user to "Install it with: hermes pm install
--extra anthropic". PM often HAS installed it: sync_venv succeeds into a new
dependency environment that only activates at process boot, and
ensure_import raises "installed; restart Hermes". A lazy-install guard
("this process is not running from the install's dependency environment")
was flattened the same way. Users were told to install something that was
installed, or given a command that doesn't address the actual refusal.

Keep the import as the decider, but remember the InstallError and put its
text in the ImportError. bedrock_adapter._require_boto3 had the identical
shape; azure_identity_adapter already propagates str(exc) and is the model.

agent/anthropic_adapter.py

@@ -34,20 +34,20 @@ from hermes_cli.version_info import get_version_info
 # ``import anthropic`` is deliberately NOT at module top: the SDK costs ~220 ms of imports and
 # every usage site is a cold user-triggered path. ``...`` = not yet tried; None = tried, missing.
 _anthropic_sdk: Any = ...
+# Why the lazy install did not make the SDK importable. A completed install that needs a restart
+# (PM activates a new dependency environment only at boot) must not be reported as "install it".
+_anthropic_install_error: Optional[Exception] = None
 
 
 def _get_anthropic_sdk():
     """Return the ``anthropic`` SDK module, importing lazily. None if not installed."""
-    global _anthropic_sdk
+    global _anthropic_sdk, _anthropic_install_error
     if _anthropic_sdk is ...:
         try:
             from pm import ensure_import
             ensure_import("anthropic")
-        except ImportError:
-            pass
-        except Exception:
-            # InstallError — fall through to ImportError handling below
-            pass
+        except Exception as exc:  # the import below decides; exc explains a miss
+            _anthropic_install_error = exc
         try:
             import anthropic as _sdk
             _anthropic_sdk = _sdk
@@ -59,6 +59,9 @@ def _get_anthropic_sdk():
 def _require_sdk(purpose: str, verb: str = "Install it with"):
     """``_get_anthropic_sdk()`` or ImportError naming the feature that needs it."""
     sdk = _get_anthropic_sdk()
+    if sdk is None and _anthropic_install_error is not None:
+        raise ImportError(f"The 'anthropic' package is required for {purpose}: "
+                          f"{_anthropic_install_error}") from _anthropic_install_error
     if sdk is None:
         raise ImportError(f"The 'anthropic' package is required for {purpose}. {verb}: "
                           f"{install_hint('anthropic')}")

agent/bedrock_adapter.py

@@ -87,6 +87,7 @@ _MIN_BOTO3_VERSION = (1, 34, 59)
 
 def _require_boto3():
     """Import boto3; converse_stream() needs >= 1.34.59 (a system boto3 can shadow the venv pin)."""
+    install_error = None
     try:
         # boto3 left [all] (PRs #24220, #24515); PM installs the [bedrock] extra on first use. This
         # runs at the first client build, never at import: an import-time sync would rebuild the
@@ -94,14 +95,14 @@ def _require_boto3():
         try:
             from pm import ensure_import
             ensure_import("bedrock")
-        except Exception as exc:  # the import below reports the real failure
+        except Exception as exc:  # the import below decides; exc explains a miss
             logger.warning("boto3 lazy install did not complete: %s", exc)
+            install_error = exc
         import boto3
     except ImportError:
-        raise ImportError(
-            "The 'boto3' package is required for the AWS Bedrock provider. "
-            f"Run: {install_hint('bedrock')}"
-        )
+        # A completed install that needs a restart must not be reported as "install it".
+        reason = f": {install_error}" if install_error else f". Run: {install_hint('bedrock')}"
+        raise ImportError(f"The 'boto3' package is required for the AWS Bedrock provider{reason}") from install_error
     try:
         version = tuple(int(x) for x in boto3.__version__.split(".")[:3])
     except (AttributeError, ValueError):