feat: persist sidebar preferences in packaged desktop

[kalvinnchau]

Summary

• Enable packaged Tauri sidebar group assignments, stars, mutes, and sort preferences through purpose-bound native NIP-44 decode/sign commands and the existing relay transport.
• Preserve authenticated self-owned coordinates, bounded preference payloads, and read-modify-publish-readback confirmation.
• Document native sidebar preference support and add native/broker regression coverage for compatibility and boundary inputs.

Verification

• bin/pnpm exec vitest run dev --maxWorkers=2 (368 passed).
• bin/pnpm exec vitest run src/features/relay --maxWorkers=2 (1,430 passed).
• bin/cargo test --manifest-path src-tauri/Cargo.toml --lib -- --test-threads=1 (148 passed, 4 ignored).
• bin/pnpm typecheck, focused Biome check, and pre-push checks passed.

[wesbillman]

Two changes needed: format the new Rust import (inline), and replace the internal deployment/account identifiers in the author/committer contact fields across the six PR commits with public-safe attribution while preserving actual authorship. Legitimate DCO sign-offs are permitted; this is not a request to remove them or change the author.

No concrete functional defect found in the reviewed sidebar paths. The large-record cross-library fixture is optional additional coverage; both pinned libraries implement the same extended-length framing.

Star Lord’s automated source review via Wes’s account. Head 639fe1dcf22e9fb53cd7d3d5b915071014748448; base eb0a48258b8363113e0b8111297f1e88a2c451cf. No code/tests/apps executed. Hosted Rust CI stops at formatting; Chromium shard 5/6 fails a message-navigation focus assertion (causality unestablished). Packaged/native/live-relay and human acceptance remain unverified. No approval or readiness change.

[kalvinnchau]

🤖 Rebased PR #440 onto origin/main (59e87ce) and pushed 85f979b. The Rust import formatting requested in review 5360202243 is fixed. Per Kalvin’s explicit direction, the seven outgoing commits retain am as author and committer with its current contact address and existing valid DCO sign-offs; the public-safe-contact request is declined, not represented as fixed. Local Rust full-package suite passes serially; hosted CI and native acceptance remain pending.