docs(about): Add v0.7.1 to the in-app changelog

The About page changelog is a hardcoded array, so it did not list v0.7.1
even though the title bar and About header already read 0.7.1 (those come
from the assembly version).

Also rework docs/release-notes/v0.7.1.md to the house format: New features
before Bug fixes, bold group headings, and the standard Downloads table.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MKF7C75bhA4ArQhyMpnsxU

src/ETTerms/App/AboutView.cs

@@ -183,6 +183,14 @@ public sealed class AboutView : UserControl
 
     private static readonly ChangelogEntry[] Changelog =
     [
+        new("0.7.1", new DateOnly(2026, 7, 16), "Scripts no longer hang when a booting device swallows a command",
+        [
+            "Fixed: a device that is still booting can silently throw away what you send it, the moment its shell takes over the console — the line never echoes and never runs, so the wait after it sat there forever and your test rig was dead until someone noticed. Adding a pause before the send only made it rarer: in one overnight 45-cycle power-cycle run, 3 cycles still hung this way.",
+            "New scripting command: sendlnretry '<text>' '<confirm keyword>' [max attempts] — it sends, waits for proof the device actually ran the command, and sends again if that proof never arrives. Leave the attempt count out and it keeps trying until it gets through.",
+            "Use it anywhere you currently send a command right after a boot: sendlnretry 'tpm2' 'TPM 2p0' followed by wait 'PASS'. Pick the confirm keyword from the command's own output, not its echo — an echo comes from the device's tty and doesn't prove the command was ever read.",
+            "If it runs out of attempts, result is 0 and the script carries on, so you can handle the failure yourself. Each attempt waits 3 seconds, or your timeout / mtimeout if you've set one.",
+            "See docs/ttl-script-reference.md for the full details.",
+        ]),
         new("0.7.0", new DateOnly(2026, 7, 5), "AI chat gets real bubbles, Markdown & a thinking indicator",
         [
             "The AI Chat pane now renders proper chat bubbles (your messages on the right, the AI's on the left) with full Markdown — code blocks, tables, lists and inline `code` all display nicely.",