feat: validator, bundle builder and release checks for 0.1.0

- Add tools/validate.py: validates packages, and with --correction runs
  proposed corrections through the gate against a package without
  writing anything (spec/11 §11.4). The gate now refuses a proposal that
  fails the correction schema, rule correction.schema.
- tools/load.py validates every package before loading, and with
  --bundle --built-from builds a scienting-bundle/1 with the FTS5 search
  index and bundle_meta (spec/13 §13.5). Search rows are defined per
  unit (sentence, cell, equation outside a sentence, figure-text) with
  the parent kind as context.
- Roster keys carry a role, and a key with the role owner may revoke any
  receipt (spec/08 §8.7, spec/20); roster schema, store table and the
  fixture roster updated. The checker signs a trial revocation to prove
  the rule both ways.
- A qa: receipt raises the nodes it sampled except those in its errors
  (spec/08 §8.2); the example paper's fidelity counts become 27 F3,
  13 F2, 4 F1 and 1 F0.
- The destination chooses the keyed scheme, not the text policy:
  hmac-team between the team's machines, hkdf-pages outside the team
  (spec/05 §5.8, spec/12 §12.5).
- A TextQuoteSelector must repeat the anchor's plain quote and is absent
  for hashed or keyed anchors (spec/18 §18.3).
- Add fixtures/records/suspect.json, a scienting-suspect/1 record.
- Oracle: hashes are kept incrementally and checked after every
  correction against a full recomputation; load and write refuse unsafe
  manifest paths; Ed25519, HKDF and schema validation come from the
  cryptography and jsonschema packages; canonical JSON uses the built-in
  encoder with an exact RFC 8785 fallback.
- The tools need Python 3.14 with cryptography and jsonschema; the py310
  CI environment is dropped and the workflow runs the default only.
- Resolve every [CHECK] note in the docs, READMEs and context; add
  CONTRIBUTING.md; every tool answers --help and refuses unknown options.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

spec/20-projects.md

@@ -10,7 +10,8 @@ A project, `scienting-project/1`, is the unit a team works in.
 | `paths` | Reading paths: ordered steps through documents, nodes, claims and layers, for onboarding a student or preparing a reading group. |
 | `layers`, `datasets`, `views`, `drafts` | What the project holds. |
 | `claims` | The claim namespace or bundle it uses, as the `lode` setting. |
-| `settings` | The digit rule for targeted F3 ([8.10](08-fidelity.md#810-targeted-f3)), the drift threshold ([6.6](06-anchors.md#66-drift)), the spot-check rate and minimum ([8.8](08-fidelity.md#88-spot-checks)), what happens when a right is unknown (`refuse`, the default, or `warn`), and the stage requirements in use. |
+| `settings` | The digit rule for targeted F3 ([8.10](08-fidelity.md#810-targeted-f3)), the drift threshold ([6.6](06-anchors.md#66-drift)), the spot-check rate and minimum ([8.8](08-fidelity.md#88-spot-checks)), what happens when a right is unknown (`refuse`, the default, or `warn`), and the stage requirements in use, as the `id` of their stage file ([14](14-rights.md)). |
 
 Projects are small on purpose: everything about them is designed for hundreds of documents, not millions.
-Owners sign policies ([14.2](14-rights.md#142-effective-uses)) and may revoke receipts ([8.7](08-fidelity.md#87-revocations-and-the-roster)).
+Owners sign policies ([14.2](14-rights.md#142-effective-uses)).
+Who may revoke receipts follows the roster instead: a key whose `role` in the roster is `owner` ([8.7](08-fidelity.md#87-revocations-and-the-roster)), so a project's owners hold keys with that role.