Require agent context for queued execution

[chubes4]

Summary

• require queued AI steps to resolve a real agent owner instead of falling back to flow.user_id
• require system-task steps to run with an agent by default, with an explicit SystemTask::requiresAgentContext() opt-out for internal maintenance tasks
• skip per-agent recurring tasks when no agents exist instead of scheduling a site-scoped fallback
• update focused smoke coverage for agent context propagation, missing-agent failures, and explicit maintenance opt-out

Closes #2217.

Testing

• php tests/system-task-agent-context-smoke.php
• vendor/bin/phpcs inc/Core/Steps/AI/AIStep.php inc/Core/Steps/SystemTask/SystemTaskStep.php inc/Engine/Tasks/TaskScheduler.php inc/Engine/AI/System/SystemAgentServiceProvider.php inc/Engine/AI/System/Tasks/SystemTask.php inc/Engine/AI/System/Tasks/Retention/RetentionTask.php inc/Engine/Tasks/RecurringScheduleRegistry.php tests/system-task-agent-context-smoke.php
• homeboy lint --path /Users/chubes/Developer/data-machine@issue-2217-agentless-queued-execution --extension wordpress --file inc/Core/Steps/AI/AIStep.php
• homeboy lint --path /Users/chubes/Developer/data-machine@issue-2217-agentless-queued-execution --extension wordpress --file inc/Core/Steps/SystemTask/SystemTaskStep.php
• homeboy lint --path /Users/chubes/Developer/data-machine@issue-2217-agentless-queued-execution --extension wordpress --file inc/Engine/Tasks/TaskScheduler.php
• homeboy lint --path /Users/chubes/Developer/data-machine@issue-2217-agentless-queued-execution --extension wordpress --file inc/Engine/AI/System/Tasks/SystemTask.php
• homeboy lint --path /Users/chubes/Developer/data-machine@issue-2217-agentless-queued-execution --extension wordpress --file inc/Engine/AI/System/Tasks/Retention/RetentionTask.php
• homeboy lint --path /Users/chubes/Developer/data-machine@issue-2217-agentless-queued-execution --extension wordpress --file inc/Engine/AI/System/SystemAgentServiceProvider.php
• homeboy lint --path /Users/chubes/Developer/data-machine@issue-2217-agentless-queued-execution --extension wordpress --file inc/Engine/Tasks/RecurringScheduleRegistry.php
• homeboy lint --path /Users/chubes/Developer/data-machine@issue-2217-agentless-queued-execution --extension wordpress --file tests/system-task-agent-context-smoke.php

Known verification limitation

• homeboy test --path /Users/chubes/Developer/data-machine@issue-2217-agentless-queued-execution --extension wordpress failed before tests ran because the lab WP Codebox mount did not include /wordpress/wp-content/plugins/data-machine/vendor/autoload.php.
• homeboy lint --changed-only failed in the lab snapshot because the snapshot was not a git repository, so changed-file coverage was run with explicit --file invocations instead.

AI assistance

• AI assistance: Yes
• Tool(s): OpenCode (openai/gpt-5.5)
• Used for: Investigated issue Remove or formalize agent-less queued execution fallback #2217, implemented the agent-context enforcement and explicit system-task opt-out, updated smoke coverage, and ran verification; Chris remains responsible for review and merge.

[homeboy-ci]

Homeboy Results — data-machine

Lint

✅ lint — passed

ℹ️ Full options: homeboy docs commands/lint
Deep dive: homeboy lint data-machine --changed-since 3390b3e

Artifacts and drill-down

• CI results artifact: homeboy-ci-results-data-machine-lint-quality-Linux-node24 contains immediate command JSON for this action invocation.
• Observation artifact: homeboy-observations-data-machine-lint-quality-Linux-node24 contains exported Homeboy run history for deeper queries.
• Drill-down: download the observation artifact, then run homeboy runs import <dir>, homeboy runs list, and homeboy runs findings <run-id>.
• Artifacts are attached to the workflow run: https://github.com/Extra-Chill/data-machine/actions/runs/26574943017

Test

✅ test — passed

• 589 passed
• 3 skipped

ℹ️ Auto-fix lint issues: homeboy refactor data-machine --from lint --write
ℹ️ Collect coverage: homeboy test data-machine --coverage
ℹ️ Save test baseline: homeboy test data-machine --baseline
ℹ️ Pass args to test runner: homeboy test -- [args]
ℹ️ Full options: homeboy docs commands/test
Deep dive: homeboy test data-machine --changed-since 3390b3e

Artifacts and drill-down

• CI results artifact: homeboy-ci-results-data-machine-test-quality-Linux-node24 contains immediate command JSON for this action invocation.
• Observation artifact: homeboy-observations-data-machine-test-quality-Linux-node24 contains exported Homeboy run history for deeper queries.
• Drill-down: download the observation artifact, then run homeboy runs import <dir>, homeboy runs list, and homeboy runs findings <run-id>.
• Artifacts are attached to the workflow run: https://github.com/Extra-Chill/data-machine/actions/runs/26574943017

Audit

✅ audit — passed

• dead_code — 158 finding(s)
• requested_detectors — 124 finding(s)
• intra-method-duplication — 65 finding(s)
• repeated_literal_shape — 13 finding(s)
• field_patterns — 9 finding(s)
• Taxonomy — 5 finding(s)
• Abilities — 4 finding(s)
• Flow — 4 finding(s)
• structural — 4 finding(s)
• Retention — 3 finding(s)
• Total: 402 finding(s)

Deep dive: homeboy audit data-machine --changed-since 3390b3e

Artifacts and drill-down

• CI results artifact: homeboy-ci-results-data-machine-audit-quality-Linux-node24 contains immediate command JSON for this action invocation.
• Observation artifact: homeboy-observations-data-machine-audit-quality-Linux-node24 contains exported Homeboy run history for deeper queries.
• Drill-down: download the observation artifact, then run homeboy runs import <dir>, homeboy runs list, and homeboy runs findings <run-id>.
• Artifacts are attached to the workflow run: https://github.com/Extra-Chill/data-machine/actions/runs/26574943017

Tooling versions

• Homeboy CLI: homeboy 0.200.1+c4278491
• Extension: wordpress from https://github.com/Extra-Chill/homeboy-extensions
• Extension revision: 08a10c96
• Action: unknown@unknown