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_live_fixes.py

@@ -16,9 +16,9 @@ from test_loop_milestones import RESTATE, Forge, loop_agent, say
 from test_loop_milestones import item as the_item
 from test_loop_milestones import world as world  # noqa: PLC0414 -- the fixture
 
-from nisse_dev.canonical import AssistantText, Fact
+from nisse_core.canonical import AssistantText, Fact
+from nisse_core.gitea import Comment
 from nisse_dev.delegation import Caps
-from nisse_dev.gitea import Comment
 from nisse_dev.loop.help import Helpers
 from nisse_dev.loop.items import GO_AHEAD, MERGE, WAITING, loop_of
 
@@ -231,7 +231,7 @@ def test_an_issue_assigned_again_after_its_item_closed_is_taken_again(
 
 
 def test_abandoning_a_blocked_issue_says_why_it_stays_open(tmp_path: Path) -> None:
-    from nisse_dev.gitea import GiteaError
+    from nisse_core.gitea import GiteaError
 
     class Strict(FakeGitea):
         def close_issue(self, repo: str, index: int) -> None: