Implement external intake adapters and canonical source-to-workflow provenance

[spences10]

Parent: #336

Goal

Implement provenance-preserving adapters that convert external work sources into canonical factory intake and explained route previews.

Scope

• Define an adapter contract for GitHub issues/PRs, project-management tickets, incidents/alerts, and support requests.
• Preserve source ids, URLs, authorship, timestamps, labels/severity, attachments/artifacts, requested outcomes, and update history.
• Resolve repository/project targets and policy without trusting unverified external instructions.
• Deduplicate repeated deliveries and update existing intake when the source changes.
• Derive risk, urgency, affected surfaces, requested side effects, and acceptance evidence with confidence/rationale.
• Require preview/override before workflow creation and retain a durable source-to-workflow audit trail.

Acceptance criteria

• At least GitHub plus one incident/support/PM adapter exercise the shared contract end to end.
• Duplicate events are idempotent; source updates reconcile without creating competing workflows.
• Prompt injection and untrusted attachment content cannot alter runtime policy or grant approvals.
• Route preview clearly distinguishes source facts, derived assumptions, and human overrides.
• Cancellation/closure/reopening of source work has defined workflow behavior.
• Tests cover missing repositories, conflicting labels/severity, edited tickets, duplicate webhooks/imports, and cross-project routing.

[spences10]

Implemented in f85c94e and verified against the current package. GitHub and incident intake adapters, trusted project mapping, provenance separation, preview/override, deduplication, source reconciliation, lifecycle handling, tamper-resistant ledger behaviour, prompt-injection boundaries, and cross-project protections are covered by intake.ts and its tests. Current package check passes and all 96 tests pass.