refactor!: claim references are claim:TAG

lode is renamed paperclaim. A claim reference is claim:TAG or
claim:host/TAG and a pin claim:TAG@hex6 (claimRef and claimPin in
common.schema.json, spec/18 §18.4, spec/02, spec/20); the eight-character
tags do not change. A project names its claim namespace as
claims.paperclaim, and the main example's targeted receipts take the
scope targeted:paperclaim. No old prefix or name is accepted.

paperspec build regenerated the fixtures and vectors: the claim link's and
the symbol's record IDs, the layer receipt, project.json, the two targeted
receipts and Ben's spot-check, the QA report, the inclusion proof, the log's
checkpoint and tiles, and the signature, spot-check, VRF and checkpoint
vectors. The walkthrough and examples quote the new receipt IDs.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SarHTuHhV9cS85XWy2NrLJ

spec/09-figures-tables-equations.md

@@ -94,7 +94,7 @@ A later minor version of the form may add a kind, and a consumer that meets a ki
 **A symbol** is a base, which is a letter, a Greek letter, or a font or accent command on a group (`\mathbf{F}`, `\hat{H}`), with any subscript, any superscript that names rather than raises (`R^{*}`, `A^{\dagger}`, `E^{\text{LJ}}`), and primes.
 A text group alone is a symbol too, unless it holds several words, is a condition in `cases`, or is the set under a big operator.
 A symbol's key is its canonical TeX with `\mathrm` spelled `\text`, `\ast` spelled `*`, `\prime` spelled `'`, and no space inside text: `K_r` and `K_{r}` have the key `K_{r}`, and `r_{\mathrm{eq}}` has the key `r_{\text{eq}}`.
-The key is the one a lode claim store gives a symbol, so a symbol in a paper and the same symbol in a claim have one key, and a `symbol` annotation names its symbol by it ([18.4](18-layers.md#184-bodies)).
+The key is the one a paperclaim claim store gives a symbol, so a symbol in a paper and the same symbol in a claim have one key, and a `symbol` annotation names its symbol by it ([18.4](18-layers.md#184-bodies)).
 
 **Issues** never stop the reading; each is `{code, message, at}`, with `at` the canonical TeX it is about.