deps: bump memmap2 0.9.10 -> 0.9.11 (clears RUSTSEC-2026-0186)

cargo-audit flagged memmap2 0.9.10 as unsound (RUSTSEC-2026-0186, unchecked
pointer offset); 0.9.11 is the patched release. Warning-level only (audit/deny
don't fail on it), but cheap to clear. Audit now down to the two deliberately
-accepted unmaintained warnings (audiopus_sys, paste; ignored in deny.toml).
Lockfile-only.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Cargo.lock

@@ -3682,9 +3682,9 @@ checksum = "6b947ae49db0d222b1dbc6b113ce7248a3fc3a6ca21b696717bfc000ba4484d8"
 
 [[package]]
 name = "memmap2"
-version = "0.9.10"
+version = "0.9.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "714098028fe011992e1c3962653c96b2d578c4b4bce9036e15ff220319b1e0e3"
+checksum = "d1219ed1b7f229ee7104d281dd01d6802fe28bb6e95d292942c4daacdeb798c0"
 dependencies = [
  "libc",
 ]