Resolve all README FIXMEs and enforce truncation safety

- Update Architecture tree to match actual src/ structure
- Fix settings button to have border and hover state (Clickable Affordance)
- Cap truncateMiddle to remove at most 10 chars (anti-spoofing guard)
- Raise caller floor from 10 to 32 chars for address display
- Fill in default RPC URL (ethereum-rpc.publicnode.com)
- Fix dependencies table intro (four runtime libs, not two)
- Clean up TODO section: remove all completed items

src/popup/views/addressDetail.js

@@ -191,7 +191,7 @@ function renderTransactions(txs) {
         const amountStr = tx.value
             ? escapeHtml(tx.value + " " + tx.symbol)
             : escapeHtml(tx.symbol);
-        const maxAddr = Math.max(10, 36 - Math.max(0, amountStr.length - 10));
+        const maxAddr = Math.max(32, 36 - Math.max(0, amountStr.length - 10));
         const displayAddr = ensName || truncateMiddle(counterparty, maxAddr);
         const addrStr = escapeHtml(displayAddr);
         const dot = addressDotHtml(counterparty);