online: halt and liveness wiring, forensic fallback, LAN key-service hosts

The query worker honours ctx.halt() and reports liveness (following
libfreemkv's Progress -> Liveness rename). A definitive key-service miss
allows the forensic phase fallback. LAN, loopback and link-local hosts
are allowed, vetted with libfreemkv's is_blocked_ip.
CI path-patches freemkv-unlock and runs cargo-deny from the repo dir;
Stop tests use idle bounds instead of tight wall-clock limits.

.github/workflows/qa.yml

@@ -96,7 +96,7 @@ jobs:
       - uses: freemkv/.github/.github/actions/checkout-siblings@v1
         with:
           checkout: libfreemkv freemkv-unlock
-          patch: libfreemkv
+          patch: libfreemkv freemkv-unlock
           self: freemkv-keysources
       - uses: dtolnay/rust-toolchain@master
         with:
@@ -119,7 +119,7 @@ jobs:
       - uses: freemkv/.github/.github/actions/checkout-siblings@v1
         with:
           checkout: libfreemkv freemkv-unlock
-          patch: libfreemkv
+          patch: libfreemkv freemkv-unlock
           self: freemkv-keysources
       - uses: dtolnay/rust-toolchain@stable
         with:
@@ -145,7 +145,7 @@ jobs:
       - uses: freemkv/.github/.github/actions/checkout-siblings@v1
         with:
           checkout: libfreemkv freemkv-unlock
-          patch: libfreemkv
+          patch: libfreemkv freemkv-unlock
           self: freemkv-keysources
       - uses: dtolnay/rust-toolchain@master
         with: