Summary

• Bump desktop client and TUI from 0.1.38 to 0.1.39.
• Update the server Docker release image to Elixir 1.16.3 on a verified Debian bookworm slim tag so Web Deploy no longer runs under Elixir 1.15.7.
• Refresh Cargo.lock so only xero-cli and xero-desktop package entries move to 0.1.39.

Test Plan

• git diff --check
• pnpm --dir client exec tsc --noEmit
• pnpm --dir client build
• MIX_ENV=test mix compile --warnings-as-errors
• TAURI_CONFIG='{bundle:{resources:[]}}' CARGO_INCREMENTAL=0 RUSTFLAGS='-D warnings -C debuginfo=0' cargo check --manifest-path client/src-tauri/Cargo.toml --package xero-desktop --package xero-cli --bins

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