feat: scienting-math/1 sources and derived/math.jsonl; lode references; stress fixes

Math content may say its source is in scienting-math/1's canonical TeX (form,
in no hash); derived/math.jsonl holds papermath's tree, symbols and issues,
and the validator now checks derived files. A symbol annotation names its
symbol by key; lode claim references use lode's tag and pin syntax. The zip
reader refuses entries zipfile cannot read, and checkpoint lines end in LF only.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017R7sgDNvUGWY2zFPCq2JH6

vectors/README.md

@@ -109,7 +109,7 @@ The table below uses a few terms that the chapters define:
 | `projections.jsonl` | One-sentence runs: plain, normalized, strict and lossy projections, complex keys and the three text values, and the projection as printed (`printed`) of an emended sentence. | [5.3](../spec/05-hashes.md#53-the-strict-projection), [3.6](../spec/03-nodes.md#36-the-plain-projection) |
 | `projection-groups.jsonl` | Which cases must share, or must differ in, a value: H₂O in six spellings, cm⁻¹, 10⁻³, K_r, ligatures, the micro sign, "103" against 10³, and an emended sentence against its printed text. | [5.3](../spec/05-hashes.md#53-the-strict-projection) |
 | `offsets.jsonl` | Code-point spans and their UTF-16 equivalents. | [1.5](../spec/01-conventions.md#15-character-offsets) |
-| `hashes.jsonl` | Every node of a small document, its own content and its five values. | [5.1](../spec/05-hashes.md#51-the-five-values) |
+| `hashes.jsonl` | Every node of a small document, its own content and its five values; and of a sentence whose equation and math run carry a math form, which enters no value. | [5.1](../spec/05-hashes.md#51-the-five-values), [5.2](../spec/05-hashes.md#52-own-content) |
 | `addresses.jsonl` | How addresses parse; null for invalid ones. | [6.1](../spec/06-anchors.md#61-addresses) |
 | `keyed.jsonl` | The team key and its ID, an HMAC, page hashes, a page-derived key, and what someone without the paper cannot check. | [5.8](../spec/05-hashes.md#58-keyed-hashes) |
 | `fingerprints.jsonl` | Pages as text lines, the stamp rules that fired, and the fingerprint; two downloads that must agree, and a change that must not. | [7.1](../spec/07-geometry.md#71-page-fingerprints) |
@@ -138,7 +138,7 @@ A candidate format changes only with a recorded reason and a new or changed vect
 
 A passing run shows one thing: for these inputs, your implementation computes the same values as the reference implementation in `src/paperspec/`.
 That code computed the expected outputs, and `pixi run build` regenerates them ([tools/](../tools/README.md)).
-The vectors hold 329 cases in all, some of them small: `hashes.jsonl` has one document, `alignment.jsonl` two pairs of readings, `offsets.jsonl` two cases.
+The vectors hold 330 cases in all, some of them small: `hashes.jsonl` has two documents, `alignment.jsonl` two pairs of readings, `offsets.jsonl` two cases.
 
 The vectors do not show the following.