Add bounded browser evidence inspection

[iperev]

Summary

• Add bounded Coverage inspection with child-owned evidence, exact omission counts and explicit questions.
• Add diff summaries and traceability inspection: directed diagrams, equivalent records, evidence-plane and one-hop filters, and explicit navigation to out-of-page targets.
• Preview, copy and download exact server-created handoff JSON without losing numeric source tokens, drafts, generation ownership or denial/staleness locks.
• Synchronize native contract source bindings and the independent release-note expectations for version 0.13.0.

Verification

The full npm run check passed on clean commit
dc8fe6b7b2ceacf6b2480078ed4b14403aa2943b, with the pinned npm 12.0.2:

• Go tests, formatting, vet, staticcheck, actionlint and govulncheck;
• command contracts/families, source/text policy, Mermaid and browser static checks;
• 315/315 native browser tests across Chromium, Firefox and WebKit;
• package artifact, self-hosting receipt/coverage and release closeout;
• 108/108 requirements bound, 358 scenarios, 91 commands;
• committed diff hygiene and an independent replay of all 77 native source bindings.

Fresh five-lane source review covered architecture, authority, checklist,
governance and test oracles. A separate three-lane review checked the shared
fixture repair. Neither wave retained a confirmed finding; static review does
not itself establish native execution. Full execution is recorded separately.
Targeted release-note tests retain deletion, substitution, surplus, ordering and
placement counterfactuals. Native Retry and directed-geometry controls also
passed 9/9 after isolating their independently specified fixture datasets.

Retained native observer evidence includes eight selected counterfactuals:
directed endpoint reversal; source-only and target-only displacement; extra SVG
line; line-local transform; endpoint-pair deduplication; stale clipboard completion;
and current-copy carrier clearing. These are bounded native witnesses, not a claim
of complete mutation adequacy or universal correctness.

Boundaries

Browser views and exported packets remain derived presentation, not proof,
execution or approval authority. Graph filters affect the returned page only.
Exact-number support depends on native JSON source-token/raw-value capabilities;
unsupported clients report unavailable rather than rounded coordinates.
Previously exported bytes are not revoked by navigation. Physical mobile OS
behavior, publication and deployment are separate evidence classes.

No temporary design, implementation-plan, review-runtime or pilot artifacts are
included in the product change. Later front-door, README, re-pilot and conditional
source-codec work remain separate phases.