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

fixtures/records/project.json

@@ -1 +1 @@
-{"claims":{"lode":"amber"},"datasets":["ds-hale-bond-params","ds-hale-ctct-scan"],"documents":[{"doc":"smithlab/hale2026harmonic-damb","reason":"The bond constants we start from.","status":{"Ben Example":"read","Cara Example":"reading"},"tags":["parameters"]},{"doc":"okafor2025solvent-acth","reason":"Solvent shifts for the validation set.","tags":["spectra"]}],"drafts":["smithlab/writer2027fixed-ynr7.v3"],"format":"scienting-project/1","key":"smithlab-charges","layers":["tag:scient.ing,2026:layer:smithlab/kp4m2x7q"],"members":[{"keys":["ana"],"person":"Ana Example","role":"owner"},{"keys":["ben","ben-spot"],"person":"Ben Example","role":"editor"},{"keys":["cara"],"person":"Cara Example","role":"reader"}],"name":"Charges and bonds","paths":[{"id":"onboarding","steps":[{"note":"Read the introduction.","ref":"smithlab/hale2026harmonic-damb","type":"document"},{"note":"Then the table.","ref":"smithlab/hale2026harmonic-damb#hj4s7pb","type":"node"},{"note":"The bond force constant, amber/k-bond.","ref":"lode:272XTX7C","type":"claim"}],"title":"First week"}],"settings":{"digit_rule":"anchored-sections","drift_threshold":"0.25","log":{"origin":"scient.ing/log/smithlab","threshold":1,"witnesses":["wit"]},"rights_unknown":"refuse","spot_check":{"minimum":10,"rate":"0.05"},"stages":"scienting-stages-default"},"store":"smithlab","views":["ctct-scan"]}
+{"claims":{"paperclaim":"amber"},"datasets":["ds-hale-bond-params","ds-hale-ctct-scan"],"documents":[{"doc":"smithlab/hale2026harmonic-damb","reason":"The bond constants we start from.","status":{"Ben Example":"read","Cara Example":"reading"},"tags":["parameters"]},{"doc":"okafor2025solvent-acth","reason":"Solvent shifts for the validation set.","tags":["spectra"]}],"drafts":["smithlab/writer2027fixed-ynr7.v3"],"format":"scienting-project/1","key":"smithlab-charges","layers":["tag:scient.ing,2026:layer:smithlab/kp4m2x7q"],"members":[{"keys":["ana"],"person":"Ana Example","role":"owner"},{"keys":["ben","ben-spot"],"person":"Ben Example","role":"editor"},{"keys":["cara"],"person":"Cara Example","role":"reader"}],"name":"Charges and bonds","paths":[{"id":"onboarding","steps":[{"note":"Read the introduction.","ref":"smithlab/hale2026harmonic-damb","type":"document"},{"note":"Then the table.","ref":"smithlab/hale2026harmonic-damb#hj4s7pb","type":"node"},{"note":"The bond force constant, amber/k-bond.","ref":"claim:272XTX7C","type":"claim"}],"title":"First week"}],"settings":{"digit_rule":"anchored-sections","drift_threshold":"0.25","log":{"origin":"scient.ing/log/smithlab","threshold":1,"witnesses":["wit"]},"rights_unknown":"refuse","spot_check":{"minimum":10,"rate":"0.05"},"stages":"scienting-stages-default"},"store":"smithlab","views":["ctct-scan"]}