v1.2.7: SNI cert fix mirrored to Android + tunnel-node scaffold (via #92 + #93)

- Android DEFAULT_SNI_POOL: mirror the Rust-side fix from #92 —
  accounts.googl.com replaced by accounts.google.com. Same cert-SAN
  mismatch that was failing every Nth rotation in the Rust client
  affected the Android user's sniHosts population; both pools need
  to stay in sync by design.

- Release rolls up PR #92 (cert fix) and PR #93 (tunnel-node +
  CodeFull.gs scaffolding). PR #93 adds a standalone binary under
  tunnel-node/ plus an Apps Script companion; no main-crate changes,
  so this is a zero-risk merge. Users who want to deploy a tunnel
  node can start today. The dispatch that activates `mode: full` is
  still in review in PR #94.

Cargo.lock

@@ -2186,7 +2186,7 @@ dependencies = [
 
 [[package]]
 name = "mhrv-rs"
-version = "1.2.6"
+version = "1.2.7"
 dependencies = [
  "base64 0.22.1",
  "bytes",