Roles, capability profiles and help on the new loop (M2.6)

- roles.driver (unset: the planner's model) and roles.classifier (unset:
  the expert's); the mapping is pinned when an item opens, and the driver
  and the go-ahead reader run on the item's own (L9).
- profiles: in configuration (tools, strengths, weaknesses), used in
  briefings: the driver's instructions say what its helper and expert are
  good at, the helper's brief who reads its handback; never a model name.
- delegate(task) and ask_expert(question) for the driver. A helper works
  on a branch off the milestone's; on a handback its work comes back as
  uncommitted changes, otherwise it is discarded, so harness branches
  never hold commits only the clone has. ask_expert keeps its budget.
- Triggers: failure_limit failed commands in a row (Driver's new "stuck"
  outcome) or the turn cap, mid-milestone, call a helper in once per
  milestone; if it fails too, the item waits on the operator. A
  delegation cut off by a crash is discarded at boot.
- Evaluation capture: delegations and ask_expert as before, and the
  reader's verdicts as classifier pairs.

Tests: help tests (merge-back, discard, needs a milestone, the stuck
trigger and its once-per-milestone limit, the expert and its budget,
pinning, briefings by profile, boot discarding a cut-off delegation),
config tests for roles and profiles, and the walk delegating with a
scripted helper that sometimes fails, with a delegations_settle property.
The walk found helper commits stranded on a merged PR's branch, fixed by
returning a helper's work uncommitted.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PPQ14L3LikyefCMFBqEbKE

nisse-dev/src/nisse_dev/loop/build.py

@@ -15,11 +15,14 @@ from nisse_dev.agent import (
     remote_url,
 )
 from nisse_dev.cancel import Cancel
+from nisse_dev.catalog import select_client
 from nisse_dev.config import AgentConfig, ConfigError
 from nisse_dev.config import Project as ProjectEntry
+from nisse_dev.delegation import Caps
 from nisse_dev.gitea import GiteaClient
 from nisse_dev.loop.agent import LoopAgent, Project
 from nisse_dev.loop.driver import Driver
+from nisse_dev.loop.help import Helpers
 from nisse_dev.loop.milestones import Milestones
 from nisse_dev.loop.reader import GoAheadReader
 from nisse_dev.matrix import MatrixTransport
@@ -124,14 +127,28 @@ def build_loop_agent(
         project_runtime(config, entry, store, gitea, account)
         for entry in config.projects
     ]
-    normalized, _passthrough = make_llm_clients(config, catalog)
+    normalized, passthrough = make_llm_clients(config, catalog)
     cancel = Cancel()
-    # The driver is the planner's model for now (M2.6 brings the driver role).
+    # The configured driver; each work item runs on the one it pinned (L9).
     driver = Driver(
         normalized,
-        config.roles.resolve("planner"),
+        config.roles.resolve("driver"),
         max_turns=config.tuning.executor.max_turns,
         cancel=cancel,
+        failure_limit=config.tuning.executor.failure_limit,
+    )
+    tuning = config.tuning
+    helpers = Helpers(
+        client=normalized,
+        roles=config.roles,
+        client_for=lambda model: select_client(model, normalized, passthrough, catalog),
+        caps=Caps(
+            turns=tuning.delegation.max_turns,
+            tokens=tuning.delegation.max_tokens,
+            wall_clock_s=tuning.delegation.wall_clock_s,
+        ),
+        expert_budget=tuning.expert.consult_budget,
+        profiles=config.profiles,
     )
     transport = MatrixTransport(config.matrix)
     loop = LoopAgent(
@@ -147,9 +164,9 @@ def build_loop_agent(
         cancel=cancel,
         oplog=oplog,
         roles=config.roles.pinned(),
-        # The driver's model reads plain-language go-aheads until the
-        # classifier role arrives (M2.6).
-        reader=GoAheadReader(normalized, config.roles.resolve("planner")),
+        # The classifier role reads plain-language go-aheads (L5, L9).
+        reader=GoAheadReader(normalized, config.roles.resolve("classifier")),
+        helpers=helpers,
         reload=lambda known: [
             project_runtime(config, entry, store, gitea, account)
             for entry in (load or _from_file(config))().projects