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

docs/comparison.md

@@ -428,7 +428,7 @@ Keep using it as a reading and distribution format.
 *Status.*
 The specification is version 0.1.0.
 `registry/formats.json` lists 32 formats: 19 are `candidate` (complete, with vectors and fixtures, ready to implement) and 13 are `provisional` (complete; expected to change as implementations gain experience): project, bundle, dataset, digitization, view, snapshot, draft-ids, exercise, submission, grade, checklist, log-entry and checkpoint ([spec/00 §0.4](../spec/00-introduction.md#04-status)).
-The repository holds 24 chapters, 42 JSON Schemas, 25 vector files, five valid fixture packages, one of them also zipped, and 31 invalid ones, each naming the rule it breaks, and a reference checker, `paperspec check`.
+The repository holds 24 chapters, 43 JSON Schemas, 25 vector files, five valid fixture packages, one of them also zipped, and 31 invalid ones, each naming the rule it breaks, and a reference checker, `paperspec check`.
 Licenses: prose CC BY 4.0; schemas, SQL, the JSON-LD context, registries, vectors and fixtures CC0 1.0; the code in `src/` Apache-2.0 ([README.md](../README.md#licenses)).
 
 *No adoption claim.*

docs/concepts.md

@@ -434,7 +434,7 @@ hale2026harmonic-damb/
   provenance.json        tools, versions and where each stage ran
   assets/                images, by SHA-256
   datasets/              datasets reported from the document
-  derived/               MathML and other renderings, rebuildable
+  derived/               MathML, math trees and other renderings, rebuildable
 ```
 
 Only `MANIFEST.json`, `document.json`, `nodes.jsonl`, `witnesses.json` and `provenance.json` are required, and an optional file with no records is left out; the example package omits `suspects.jsonl`.

docs/glossary.md

@@ -100,6 +100,11 @@ Match hash
 Two readings agree only when their match hashes are equal and their complex-notation keys are equal.
 A complex-notation key is `notation:source` for a piece of math too complex for the formats to normalize, with the source's whitespace removed ([5.3](../spec/05-hashes.md#53-the-strict-projection)). ([5.1](../spec/05-hashes.md#51-the-five-values), [5.3](../spec/05-hashes.md#53-the-strict-projection))
 
+Math form
+:   A standard spelling of formulas, so that one formula is written alike in every paper and claim.
+`scienting-math/1` is canonical TeX, with a tree read from it and a key for each symbol; papermath implements it.
+An equation or math run in the form says so with `form`, which enters no hash, and its tree lives in `derived/math.jsonl`. ([3.7](../spec/03-nodes.md#37-math-forms), [9.4](../spec/09-figures-tables-equations.md#94-the-math-form))
+
 ML-DSA-65
 :   Outside term.
 The lattice-based signature scheme of FIPS 204, believed to resist quantum computers.
@@ -172,6 +177,10 @@ Strict projection
 Suspect
 :   A doubtful reading raised for a person or a review session to answer. ([5.7](../spec/05-hashes.md#57-suspects))
 
+Symbol key
+:   The name of a symbol in a formula, its canonical TeX with `\mathrm` spelled `\text`: `K_{r}` for `K_r`.
+A paper's symbols and a lode claim's have one key, so a `symbol` annotation names its symbol by it. ([9.4](../spec/09-figures-tables-equations.md#94-the-math-form), [18.4](../spec/18-layers.md#184-bodies))
+
 Targeted F3
 :   Proofreading the nodes a team's claims, quotations and datasets rest on, rather than every node.
 The target set also includes the leaves of every anchored container, every equation and, under the project's digit rule (`all`, `anchored-sections` or `none`), sentences and cells with a digit in a text or math run (an inline stretch of plain text, or of TeX or Typst math, within the node; [3.5](../spec/03-nodes.md#35-inline-runs)). ([8.10](../spec/08-fidelity.md#810-targeted-f3))

docs/overview.md

@@ -52,7 +52,7 @@ It appears inside hashed data and test vectors, and it is separate from the repo
 | Folder | Holds |
 | --- | --- |
 | [spec/](../spec/README.md) | The specification, in 24 chapters (00 to 23). Normative. |
-| [schemas/](../schemas/README.md) | 42 JSON (plain-text data format) Schemas for the files and records. |
+| [schemas/](../schemas/README.md) | 43 JSON (plain-text data format) Schemas for the files and records. |
 | [registry/](../registry/README.md) | The list of formats, the rule IDs a checker reports, download-stamp rules, and default rights requirements. |
 | [tools/](../tools/README.md) | How to run the reference commands: `paperspec check` checks everything, `paperspec build` rebuilds the fixtures and vectors, and `paperspec load` loads packages into SQLite. |
 | [src/paperspec/](../src/paperspec/) | The oracle, a compact implementation of every rule, which the other repositories of the project install as the Python package `paperspec`. |