P1 pilot: add lingcod_msy_recovery.csv with its manifest

[mmcky]

Pilot P1 — local-path static (QuantEcon/meta#338). The first dataset to land in the published tree, and the first manifest written against the schema. Paired with QuantEcon/lecture-python-intro#792, which repoints the lecture.

Stacked on #10 (the Phase 2 restructure) — lectures/ does not exist on main until that merges. Base retargets to main automatically once #10 lands. Review #10 first.

(Supersedes #11, which was opened on a data/… branch. Renamed so both halves of P1 share a branch name per the workspace convention — lecture-python-intro has a stale branch literally named data, and git cannot hold both a ref data and a directory data/. No content change.)

Licence — cleared before adding

RAM Legacy is CC BY 4.0, attribution-only, so rehosting this extract is permitted. How that was established is itself a finding: ramlegacy.org states no licence at all. The authority is the Zenodo record behind its DOI (license: cc-by-4.0, access_right: open), confirmed two ways. "Check the homepage" is not a sufficient licence procedure — so the manifest records when and against what a licence was established. An undated licence claim is not evidence.

What meeting a real file did to the schema

The sketch in #10 was written from a clean example. One actual dataset broke it in three places, each folded back into manifest-schema.yml:

Finding	Change
Lingcod is a byte-perfect copy of what the lecture consumes, yet its upstream provenance cannot be re-derived at all	integrity splits into migration and upstream. A single verified field would have to overstate or understate this file
The file is constructed but ships no builder — the exact bug AGENTS.md names. The tempting fix is to relabel it verbatim, which buries the gap	builder_status: unrecovered, so it stays visible in the generated catalog. One of the constructed-but-unscripted set PLAN Phase 9 tracks
F_over_Fmsy is null in the terminal assessment year — correct, and normal	known_nulls, so Phase 5's invariant tests can enforce "no unexpected nulls" without a blanket rule rejecting this file

Integrity

Axis	Status	Basis
migration	verified	sha256 fc2f873f… byte-identical to intro's copy, so the repoint cannot change lecture output
upstream	unverifiable	the extract records no stock id, no database version, no transformation — nothing to re-derive from

Recording unverifiable with a reason is deliberate: PLAN Phase 7 says not to promote a file whose integrity status is unknown, and "we checked, and it cannot be checked" is a known status. Silence would not be.

Data

82 rows, 1928–2009, year / B_over_Bmsy / F_over_Fmsy. Verified readable over https and renders the lecture's figure unchanged.

Part of QuantEcon/meta#338
See QuantEcon/meta#336

[Copilot]

Pull request overview

This PR adds the first “P1 pilot” dataset to the new published lectures/ tree—lingcod_msy_recovery.csv—together with its sidecar manifest, and updates manifest-schema.yml based on lessons from this first real manifest.

Changes:

• Extend manifest-schema.yml to split integrity into migration vs upstream, add license.verified, add schema.known_nulls, and introduce builder_status.
• Add lectures/lingcod_msy_recovery.csv and its manifest lectures/lingcod_msy_recovery.csv.yml.
• Record the pilot dataset’s provenance, schema, consumers, integrity assessment, and known nulls in the new manifest.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
manifest-schema.yml	Updates the manifest schema template to reflect pilot-driven requirements (integrity split, known nulls, builder status, license verification date).
lectures/lingcod_msy_recovery.csv.yml	Adds a full per-dataset manifest (source/license/integrity/schema/consumers/builder fields).
lectures/lingcod_msy_recovery.csv	Adds the lingcod MSY recovery time series data used by the consuming lecture.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.