perf(gui): memoize Monero subaddress rows

[shriram-svg]

Summary

• Extract the Monero subaddress table row into a memoized component.
• Stabilize the label-change handler with useCallback.
• Keep unchanged rows from re-rendering while editing one subaddress label, which avoids rebuilding address/copy/balance cells for the whole list on every keystroke.

Validation

• corepack yarn install --immutable
• corepack yarn eslint src/renderer/components/pages/monero/SubaddressesModal.tsx --quiet
• PATH="$HOME/.cargo/bin:$PATH" corepack yarn gen-bindings
• corepack yarn tsc
• git diff --check

Bounty: #727. If this is accepted for a bounty award, I can provide the payout address requested by the maintainer.

[Einliterflasche]

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