Implement atomic pairwise commit plans

[AndriGitDev]

Summary

• Generalize the retained ordinary pairwise-receive transaction from Harden core trust boundaries and delivery reliability #77 into bounded typed plans for pairwise send/receive, handshake receive, receipt receive, and maintenance.
• Commit detached ratchet and prekey candidates in one BEGIN IMMEDIATE transaction with history/control state, replay markers, receipt routes, outbound envelopes, delivery rows, schedules, capabilities, expiry/tombstones, and exact deferred-row acknowledgement.
• Replace live state only after a commit receipt and retain a sealed presentation marker for deterministic snapshot resynchronization after commit-before-notification restarts.
• Add deterministic crypto, statement, commit, memory, event, disk-full, constraint, duplicate, reorder, restart, expiry, repair, and deferred-input crash cases.

Scope and status

The implemented slice covers ordinary and versioned pairwise text, edits, attachment offers, ephemeral content, capability controls, receipts, scheduled activation, late-device delivery, reset handshakes, unconfirmed-session repair, retry/expiry maintenance, and view-once tombstones.

ADR-0028 remains Proposed. GroupSend and GroupReceive, atomic deferred group/media follow-up, and ADR-0030 first-contact quarantine remain open. Real-time call state remains process-local.

Validation

• strict workspace clippy and default all-target checks
• all-feature kult-store, kult-node, and kult-ffi suites
• deterministic transaction, crypto, memory, event-delivery, and restart matrices
• daemon event-wire tests
• formatting, documentation, release-version, dependency-policy, no-default-feature, and desktop JavaScript checks
• 100k and 1m opaque-store scale gates within their budgets

Environment limits

• Full workspace execution reaches host restrictions on multicast and Unix-domain socket creation; permission-expanded reruns produced the same EPERM results.
• Standalone desktop Rust linking requires GTK/GLib development packages that are not installed in this environment.