fix(akroasis): correct Pinax authority boundary

[forkwright]

Summary

• reserve Pinax for the standalone fleet relational engine and keep Akroasis's reference-library application name neutral pending a distinct Gnomon-approved identity
• remove the unused staged Sphragis dependency, its exact dead-dependency baseline row, and the obsolete workflow token rationale; Cargo.lock never contained Sphragis
• define the authority split: Pinax owns transactions, typed schemas, and page-at-rest encryption; Akroasis owns the application/domain-envelope policy; Sphragis owns recipient key distribution
• replace the obsolete local-fjall reference-store premise while preserving the historical security(reference-library): enforce domain envelopes over Pinax page encryption #132 document path for durable links
• make the README, architecture, project index, lexicon, reference-layout note, docs manifest, and akroasis know placeholder agree; explicitly forbid a local crates/pinax identity

Tracker reconciliation

• References feat(reference-library): integrate Pinax persistence with Sphragis key epochs #395: retitled and rewritten around the standalone Pinax dependency, async-native multi-record transaction and typed-schema producer gates, a default-off Akroasis preview feature, exact reviewed Sphragis handoff, and a permanent hazmat prohibition.
• References lint: remove the remaining baseline entries and delete the baseline #261: this change removes only the exact ARCH/substrate-dead-dep row, moving the measured baseline from 24 entries to 23; it does not weaken or complete that issue.
• References security(reference-library): enforce domain envelopes over Pinax page encryption #132: re-triaged without closing so Pinax owns page-at-rest encryption and Akroasis owns only typed domain-envelope policy. The original write/read/migration/adversarial acceptance remains represented.

Verification

• cargo fmt --all
• cargo fmt --all -- --check
• git diff --check
• git diff --exit-code -- Cargo.lock
• confirmed crates/pinax does not exist
• confirmed .kanon-lint-baseline.toml contains 23 entries
• no compile, test, or gate command was run on Metis, per operator direction

Collision and residual gates

• Open release PR chore(main): release 0.6.2 #465 also changes Cargo.toml; it was inspected and left untouched. This branch is based on live main at d4ac3c5f24121ac3aeef0aca5b6baabf82f51f03.
• Durable implementation still waits for standalone Pinax's Tokio-native API, atomic multi-record transactions, and typed schemas.
• Preview fixtures may remain default-off before Sphragis docs: README.md has stale status, Tauri references, em dashes, Title Case, first-person singular #43 completes. Any reviewed/default promotion waits for docs: README.md has stale status, Tauri references, em dashes, Title Case, first-person singular #43's favorable disposition and exact consumer-handoff tag.
• The remaining 23 baseline entries stay owned by lint: remove the remaining baseline entries and delete the baseline #261 and their recorded producer/review gates.