nisse-core: group modules into packages by architecture section

A pure move; behaviour unchanged.

- models (L9, L7): llm, catalog, probe, render, render_anthropic, context
- log (L7, L6): canonical, views
- state (L8): store (was state), reconcile, worker, cancel, dump
- knowledge (L10, L6.4): vault, memory
- conversation (L5): transport, matrix
- execution (L13): ssh (was execution), testing
- authority (P3, P4, L4): actions
- gitea, oplog, envfile stay at the top until each gains a second module.

Every import, monkeypatch target, script and doc reference rewritten.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01J5Utyfzw7gF7UhjRDEtjTk

scripts/probe_context.py

@@ -5,7 +5,7 @@
 ALIAS is a LiteLLM model alias. The LiteLLM URL and token come from the agent
 config (NISSE_CONFIG, ./nisse-dev.yaml, or --config), with its secrets from
 the environment or .env. See docs/Tuning-Guide.md, "Declaring a local model's
-limits", and nisse_core/probe.py for what the verdicts mean.
+limits", and nisse_core/models/probe.py for what the verdicts mean.
 """
 
 import argparse
@@ -15,9 +15,9 @@ from pathlib import Path
 
 import httpx
 
-from nisse_core.catalog import ModelCatalog
 from nisse_core.envfile import load_env_file
-from nisse_core.probe import probe
+from nisse_core.models.catalog import ModelCatalog
+from nisse_core.models.probe import probe
 from nisse_dev.config import AgentConfig, ConfigError