docs(archive): Maji PR preservation discipline for recent merged PRs

[AceHack]

Autonomously archived recently merged PRs 4073, 4072, 4071, 4067, 4059 as per Maji protocol.

[Copilot]

Pull request overview

Adds git-native PR discussion archives under docs/pr-discussions/ for a batch of recently merged PRs, aligning with the repo’s PR-preservation protocol (manual runs of tools/pr-preservation/archive-pr.ts).

Changes:

• Add PR conversation archives for PRs #4073, #4072, #4071, #4067, and #4059 (frontmatter + description + reviews/threads/comments).
• Standardize archive metadata to the current archive-pr.ts schema (archived_at, archive_tool, merged timestamps, etc.).

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
docs/pr-discussions/PR-4073-backlog-b-0156-close-as-substrate-drift-all-6-acceptance-cri.md	New archive for PR #4073 discussion (B-0156 closure).
docs/pr-discussions/PR-4072-research-persona-mika-first-in-substrate-landing-resonance-w.md	New archive for PR #4072 discussion (persona “mika” landing).
docs/pr-discussions/PR-4071-research-persona-ani-preserve-ani-grok-agora-v5-full-economi.md	New archive for PR #4071 discussion (Agora V5 preservation).
docs/pr-discussions/PR-4067-research-persona-ani-preserve-ani-grok-agora-vision-packets.md	New archive for PR #4067 discussion (Agora V1–V4 packets preservation).
docs/pr-discussions/PR-4059-substrate-imaginary-stack-rescue-step-1-cluster-for-b-0584-l.md	New archive for PR #4059 discussion (Imaginary Stack / Lean toy model thread log).

[AceHack]

Thread resolution — substrate-honest no-op (both threads):

Both Copilot findings target text in docs/pr-discussions/PR-4073-backlog-b-0156-close-as-substrate-drift-all-6-acceptance-cri.md, which is a verbatim archived preservation of PR #4073's original body content.

• Line 21 link target (../blob/main/...)
• Line 30 line-suffix path (.github/workflows/gate.yml:877)

Both appear in the original PR #4073 description. The archive's job is to faithfully preserve what shipped, not to retroactively reformat it. Per .claude/rules/blocked-green-ci-investigate-threads.md verify-also-on-stale-but-fresh-looking-findings: stale ≠ false; the action window for editing the original PR closed at merge. Resolving no-op.