M7.1: extract nisse-core

What isn't the dev agent's moves to nisse-core, unchanged in behaviour,
with its tests: canonical, render, render_anthropic, llm, catalog, probe,
context, views, state, reconcile, worker, cancel, dump, transport, matrix,
execution, testing, vault, memory, oplog, envfile and gitea (whole).

- nisse_core.state.StateStore holds the tables every agent has; an
  agent's subclass adds its tables (version, migrations), roles and
  views. nisse_dev.state.StateStore adds the build VM blocks (v5).
- views.project takes what each role is shown, rather than a fixed table.
- Vault takes the agent's name (agent=), for provenance.
- A test that nisse_core never imports an agent.
- The loop, config, git, delegation, expert, tools and evals stay in
  nisse-dev until nisse-ops has a loop to share.

Docs: the Development Plan marks M7.1 done and notes that Phase 6 waits on
the agent host and Terraform; Architecture Part L names the package.

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

nisse-dev/tests/test_loop.py

@@ -8,25 +8,25 @@ from typing import Any
 import pytest
 from model_contract import assert_renderable
 
-from nisse_dev.cancel import Cancel
-from nisse_dev.canonical import (
+from nisse_core.cancel import Cancel
+from nisse_core.canonical import (
     AssistantText,
     CanonicalEvent,
     Fact,
     ToolCall,
     ToolResult,
 )
-from nisse_dev.gitea import Issue
-from nisse_dev.llm import LLMError
+from nisse_core.gitea import Issue
+from nisse_core.llm import LLMError
+from nisse_core.oplog import OpLog
+from nisse_core.transport import InMemoryTransport
+from nisse_core.worker import InlineWorker
 from nisse_dev.loop.agent import LoopAgent
 from nisse_dev.loop.driver import Driver
 from nisse_dev.loop.items import CLOSED, GO_AHEAD, READY, RUNNING, WAITING, loop_of
 from nisse_dev.loop.reader import command_form
-from nisse_dev.oplog import OpLog
 from nisse_dev.state import StateStore
 from nisse_dev.tools import ToolOutcome
-from nisse_dev.transport import InMemoryTransport
-from nisse_dev.worker import InlineWorker
 
 DON = "@don:test"
 
@@ -250,7 +250,7 @@ def test_a_go_for_an_earlier_revision_is_not_applied(h: Harness) -> None:
     h.say("put it in its own module")  # changes, so the driver restates rev-2
     assert loop_of(h.item()).rev == 2
     # A go sent while rev-1 was on screen, arriving now.
-    from nisse_dev.transport import InboundMessage
+    from nisse_core.transport import InboundMessage
 
     h.agent.handle(InboundMessage(DON, "go", thread=h.thread()), about=1)
     assert not loop_of(h.item()).started