Visor: compound petname/glyph control and contact glyphs

[lannbot]

Summary

• Combine the glyph picker, petname input, and re-roll button into one shared control for user, app, and contact labels.
• Add private contact glyphs with atomic label saves, Save/Revert drafts, persistence, and device-group synchronization.
• Display saved contact glyphs in lists and selections; preserve local labels across imports and contact merges.
• Preserve typing during an in-flight save and retain modal search/return focus behavior.

Verification

• cargo fmt --check
• cargo test -p polyvisor-contacts-model -p polyvisor-kernel -p polyvisor-visor
• cargo clippy --workspace --all-targets -- -D warnings
• just wit
• deno task check
• just build-wasm
• just site-fixtures
• Real Chromium: deno task e2e --scenario=contacts-portable-file-import --scenario=petname-dice-and-glyph-random
• Inspected desktop/mobile screenshots; checked exact glyph persistence, combined Save/Revert, keyboard focus, mobile alignment, and pairing adoption.

Automerge will be armed after opening this PR.