Roll out the accepted layered gitignore contract through reviewed repository waves

[szmyty]

Outcome

Turn the accepted .gitignore contract into a reviewed, observable adoption wave using Pace's existing convergence pipeline. This owns rollout; Empathy owns baseline policy, Holon materialization, EgoLint conformance, and Relay CI.

Parent and execution order: egohygiene/.github#32.

Starting evidence

The Filament manual pilot is accepted in egohygiene/filament#6 at c3eb64b8087face7504e7571dc8396c19525649f. It selects only the universal root baseline from Empathy foundation 1.1.0. One accepted pilot is not proof that the repository fleet has converged.

The existing general Pace pipeline already supports deterministic drift plans, repository-sized review units, candidate verification, and a bounded PR adapter. Reuse it rather than building another updater.

Scope and acceptance

• Define the actual eligible repository inventory and maintainer-reviewed rollout wave; distinguish adopted, ready, blocked, excepted, deferred, and unknown.
• Consume immutable Empathy inputs, Holon materialization output, EgoLint content-conformance evidence, and applicable Relay execution evidence.
• Inventory existing root/nested ignore policies and preserve legitimate local content; surface uncertain migrations or weakened protection as conflicts.
• Preview one repository at a time with exact source/base revisions, allowlisted changes, before/after behavior, rollback, and review authority.
• Prove a documentation-only consumer, a language-scoped consumer, and a repository with local/nested exceptions using public-safe fixtures.
• Submit changes only through reviewed bounded PRs; preserve branch/base checks, no-op/idempotence, and no self-merge.
• Verify accepted consumer merges and actual conformance before recording adoption.
• Retain explicit exclusions and remaining debt; complete the agreed wave without falsely reporting undeployed or unknown repositories as conformant.
• Publish status through the existing observation/report contracts and update the master epic's completion ledger.

Ignore status never grants permission to remove files. Inventory and reports need path/rule/provenance evidence, not private payloads.

Dependencies — reviewed with prerequisites

Blocked for live rollout until these artifacts are accepted and available as compatible immutable inputs:

• Materialize and safely update the accepted layered gitignore contract holon#58 — preservation-safe adoption/update and recovery path.
• Validate layered gitignore content, provenance, and effective Git behavior egolint#61 — reusable semantic validator.
• Run pinned EgoLint profiles through a reusable workflow relay#49, with required-file execution coordinated through Validate architecture and repository structure in CI relay#5 — shared execution/distribution evidence for the chosen rollout mode.

The accepted Empathy baseline and Filament manual pilot satisfy the initial policy/pilot prerequisites. Planning may use immutable synthetic fixtures before live rollout is ready; such fixtures do not count as live adoption.

Coordinate EgoLint workflow rollout with #20 rather than duplicating it. The maintainer's deferral of direct MegaLinter repairs remains in force.

Review cadence

One bounded PR per review/merge/sync cycle. This issue does not authorize a fleet-wide write or bypass per-repository review. Recheck current implementations and select the smallest ready slice when scheduled.