M7.2: share the loop's parts

Shared parts, not a shared scheduler (agreed): nisse-review will have its
own small scheduler; a common one waits until two exist to compare.

- nisse_core.loop.driver: the driver run, moved; the agent names its
  waiting tools per run (nisse-dev's are WAITING_TOOLS), and execution
  goes to any Executor (ToolOutcome moves with it).
- nisse_core.loop.tools: the tool helper and the tools any agent offers
  (notes, memory, memory_done, ask_expert); nisse_core.loop.expert.
- nisse_core.knowledge.handlers: Knowledge, the vault and memory as
  control tools, the index and prompt text, out of LoopAgent.
- nisse_core.config: file reading, references, people, tuning sections of
  the agent's own, LLM numbers, the vault.
- New core tests: a driver run with a non-workspace executor and the
  agent's own waiting set; Knowledge alone; the shared config pieces.

Docs: the Development Plan marks M7.2 done; Architecture Part L and the
nisse-core README name the new parts.

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

docs/Architecture.md

@@ -136,9 +136,10 @@ Everything in this part is used by every agent. In code it is the `nisse_core`
 package: the transcript (L7) and its renderers, the LLM client and model catalog
 (L9), context fitting and per-role views (L6), the state store and reconciliation
 (L8), transports (L5), SSH execution (L13), the vault and memory (L10, L6.4),
-logging and secrets loading (L12), and the Gitea client (L1). An agent extends
-the store with its own tables, roles and views; the loop is still `nisse-dev`'s
-until a second agent shares it.
+logging and secrets loading (L12), the Gitea client (L1), shared configuration,
+and the parts of a loop (L2): the driver run, the common control tools,
+`ask_expert`, and the vault and memory as tools. An agent extends the store with
+its own tables, roles and views, and keeps its own scheduler.
 
 ### L1. The work model