v1.7.7: i686-windows + per-deployment longpoll fallback

- #288 (@amiralishoja): adds i686-pc-windows-msvc to the release
  matrix. 32-bit Windows users get mhrv-rs-windows-i686.zip on
  every release.
- #290 (@dazzling-no-more): per-deployment longpoll fallback state
  with TTL-based auto-recovery. Replaces a global AtomicBool that
  one degraded deployment could permanently flip. Now the aggregate
  legacy gate only fires when every configured deployment is marked,
  and self-corrects on TTL expiry — upgraded tunnel-nodes rejoin
  the fast path automatically. 4 new tokio::test virtual-time tests.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

docs/changelog/v1.7.7.md

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+<!-- see docs/changelog/v1.1.0.md for the file format: Persian, then `---`, then English. -->
+• اضافه شدن build برای ویندوز ۳۲ بیتی (i686-pc-windows-msvc) به matrix release ([#272](https://github.com/therealaleph/MasterHttpRelayVPN-RUST/issues/272), [#288](https://github.com/therealaleph/MasterHttpRelayVPN-RUST/pull/288)): کاربری که سیستم قدیمی ویندوز ۳۲ بیتی داشت درخواست build اختصاصی کرد. حالا artifact ‫`mhrv-rs-windows-i686.zip`‬ هم در release page موجوده. ممنون از @amiralishoja برای PR
+• رفع باگ "یک deployment معیوب همه ‍session‌ها رو روی cadence legacy گیر می‌اندازه" ([#290](https://github.com/therealaleph/MasterHttpRelayVPN-RUST/pull/290)): قبلاً وقتی یکی از deployment‌ها fast-empty (long-poll نمی‌شناخت) برمی‌گردوند، flag global `server_no_longpoll` فعال می‌شد و کل session‌ها رو روی cadence ۳۰ ثانیه‌ای legacy گیر می‌انداخت — حتی اگه deployment‌های دیگه راحت long-poll می‌کردن. اون flag همچنین هیچ‌وقت reset نمی‌شد، پس tunnel-node بازنشانده تا restart process به مسیر سریع برنمی‌گشت. **Fix:** state per-deployment با TTL ۶۰ ثانیه. flag aggregate فقط وقتی فعال می‌شه که **همه** deployment‌های یکتا mark شده باشن، و خودش رو از روی expiry self-correct می‌کنه. tunnel-node ارتقا داده شده خودش به مسیر long-poll fast بدون restart برمی‌گرده. ۴ تست جدید با `tokio::test(start_paused = true)` پوشش‌دهی timing logic. ممنون از @dazzling-no-more
+---
+• Add 32-bit Windows (i686-pc-windows-msvc) to the release matrix ([#272](https://github.com/therealaleph/MasterHttpRelayVPN-RUST/issues/272), [#288](https://github.com/therealaleph/MasterHttpRelayVPN-RUST/pull/288)): a user with a legacy 32-bit Windows machine asked for a dedicated build. `mhrv-rs-windows-i686.zip` now appears alongside the other artifacts on every release page. Thanks @amiralishoja for the PR
+• Fix "one degraded deployment drags all sessions onto the legacy cadence" bug ([#290](https://github.com/therealaleph/MasterHttpRelayVPN-RUST/pull/290)): previously, a single fast-empty observation from any one deployment flipped the global `server_no_longpoll` flag, dragging every session onto the 30-second legacy cadence even when the other deployments were happily long-polling. The flag also never reset, so a redeployed/recovered tunnel-node didn't return to the fast path until the mhrv-rs process restart. **Fix:** state is now per-deployment with a 60-second TTL. The aggregate flag flips only when **every** unique configured deployment is marked, and self-corrects on read when entries expire. An upgraded tunnel-node rejoins the long-poll fast path on its own. 4 new tests using `tokio::test(start_paused = true)` to cover the timing logic without burning real wall-clock seconds. Thanks @dazzling-no-more