[ATAC-Helicopter]

Summary

• FAD-0503: deterministic active-row sorting, pointer/keyboard interaction freeze, honest empty/unavailable states and reconnect-safe controls.
• Serialize/coalesce row commands, keep native round trips off the UI thread, guard native lifetime and show command failure feedback.
• BUG-00003: preserve omitted metadata in incremental PipeWire updates; this fixes a real rendered drag losing its application identity.
• Add reproducible optional desktop interaction testing, inspected screenshots and qualification evidence.

Closes #40.

Local validation

• Full build: zero warnings/errors; 102 managed tests, two native tests, isolated PipeWire integration.
• ASAN/UBSAN native tests and isolated command/churn/restart integration passed locally.
• 16 UI tests; six tooling tests; format, roadmap/mirror parser and whitespace checks.
• Real rendered XWayland fixture: slider drag, keyboard Home/Right, mute, disconnect during drag, connected-empty/reconnecting views, and recovered control after private daemon restart.

Evidence: docs/development/qualifying-ui-interactions.md and docs/screenshots/fad-0503-*.png.

Qualification boundary

Remote Actions are deliberately canceled at the maintainer's request because the account has exhausted its minutes. Local evidence is not represented as remote CI success; merging requires the previously authorized maintainer bypass.

BUG-00004 remains open: the normal launch stalls with this host's full Fontconfig setup. The rendered fixture uses process-local DejaVu font configuration, not a production workaround. REL-00006, output/icons, pinned/inactive persistence, tray and localization remain open. No release/tag is created.