finish(STATE-WP-0064): cut over scheduler and split sweep errors from failures

STATE-WP-0064 cutover (state-hub only):
- Retire local custodian-sync.timer; archive units under infra/systemd/archived/
- Mark workplan finished; update infra/README, cron-migration, runbook, AGENTS.md
- Point activity-core-delegation at the consistency-sweep runbook

Consistency engine — automation error vs assessment failure:
- C-00 is an automation error; C-01..C-23 assessment failures are recorded
  for follow-up but no longer fail --remote --all scheduled sweeps (exit 0)
- Skip workplans/README.md in the workplan glob (human index, not a workplan)
- Progress events and compare script expose automation_error and
  assessment_failures separately from exit_code

api/schemas/consistency_sweep.py

@@ -8,6 +8,7 @@ from pydantic import BaseModel, Field
 
 class ConsistencySweepIssueSummary(BaseModel):
     fail: int = 0
+    automation_error: int = 0
     warn: int = 0
     info: int = 0
 
@@ -39,6 +40,7 @@ class ConsistencySweepRemoteAllRun(BaseModel):
     max_seconds: int
     source: str
     exit_code: int
+    automation_error: bool = False
     lock_skipped: bool
     repos_processed: list[ConsistencySweepRepoResult] = Field(default_factory=list)
     skipped_clean: list[str] = Field(default_factory=list)