Improve Decodex App control-plane context handling

[yvette-carlisle]

Summary

• surface control-plane context-load failures as project-scoped warning details with credential setup guidance
• allow macOS GUI-launched helpers to resolve configured secrets from launchd env when process env is missing
• remove the account-panel aggregate operator totals row so runs only appear under each account

Verification

• cargo test -p decodex control_plane_context_failure_includes_project_warning_detail
• cargo make fmt
• cargo make fmt-check
• cargo make check-rust
• cargo make test
• apps/decodex-app/script/build_and_run.sh --verify
• git diff --check
• live /api/operator-snapshot readback after restart showed no warning details and enabled projects connector_state=ok