ci: add wasm32v1-none target and SKIP_WASM_BUILD to fix serde_core duplicate alloc error

The paritytech CI container lacks the wasm32v1-none target, causing
wasm-builder to fall back to wasm32-unknown-unknown with -Z build-std.
Combined with our serde_core fork, this creates a duplicate lang item
error for alloc crate.

Fix: Add rustup target add wasm32v1-none to all WASM-building jobs.
For check-only jobs (bench checks, docs, each-crate), add SKIP_WASM_BUILD=1.

Also fixes test-deterministic-wasm wasm blob path to work with either target.

.github/workflows/tests-misc.yml

@@ -113,6 +113,9 @@ jobs:
       - name: Checkout
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
 
+      - name: Install wasm32v1-none target
+        run: rustup target add wasm32v1-none
+
       - name: Clean cargo cache to free disk space
         run: |
           cargo clean 2>/dev/null || true
@@ -123,8 +126,8 @@ jobs:
         run: |
           # build runtime
           cargo build -q --locked --release -p zagros-runtime -p pezkuwichain-runtime
-          # make checksum
-          sha256sum target/release/wbuild/*-runtime/target/wasm32-unknown-unknown/release/*.wasm > checksum.sha256
+          # make checksum — find wasm blobs regardless of target triple
+          find target/release/wbuild/ -name '*.wasm' -path '*/release/*' | sort | xargs sha256sum > checksum.sha256
           cargo clean
           # build again
           cargo build -q --locked --release -p zagros-runtime -p pezkuwichain-runtime
@@ -250,6 +253,9 @@ jobs:
       - name: Checkout
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
 
+      - name: Install wasm32v1-none target
+        run: rustup target add wasm32v1-none
+
       - name: Clean cargo cache to free disk space
         run: |
           cargo clean 2>/dev/null || true
@@ -305,6 +311,9 @@ jobs:
       - name: Checkout
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
 
+      - name: Install wasm32v1-none target
+        run: rustup target add wasm32v1-none
+
       - name: script
         run: |
           cargo build --locked -p zagros-runtime --features metadata-hash
@@ -361,6 +370,7 @@ jobs:
       RUSTFLAGS: "-D warnings"
       CI_JOB_NAME: cargo-check-each-crate
       CARGO_INCREMENTAL: 0
+      SKIP_WASM_BUILD: 1
     strategy:
       matrix:
         index: [1, 2, 3, 4] # Reduced from 7 to 4 parallel jobs to lower system load