Fix CI: set RUST_MIN_STACK to prevent nargo stack overflow

The nargo binary bundled with Aztec overflows its default stack when
compiling contracts. Set RUST_MIN_STACK=8388608 (8MB) for all aztec
compile/test steps across workflows.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: critesjosh

.github/workflows/note-send-proof-tests.yml

@@ -68,6 +68,8 @@ jobs:
 
       - name: Compile contract and generate artifacts
         working-directory: note-send-proof
+        env:
+          RUST_MIN_STACK: "8388608"
         run: script -e -c "yarn ccc"
 
       - name: Generate note hash data

.github/workflows/prediction-market-tests.yml

@@ -70,11 +70,15 @@ jobs:
 
       - name: Run Noir unit tests
         working-directory: prediction-market
+        env:
+          RUST_MIN_STACK: "8388608"
         run: script -e -c "aztec test"
         timeout-minutes: 10
 
       - name: Compile contract and generate artifacts
         working-directory: prediction-market
+        env:
+          RUST_MIN_STACK: "8388608"
         run: |
           script -e -c "aztec compile"
           script -e -c "aztec codegen target -o artifacts"

.github/workflows/recursive-verification-tests.yml

@@ -79,6 +79,8 @@ jobs:
 
       - name: Compile contract and generate artifacts
         working-directory: recursive_verification
+        env:
+          RUST_MIN_STACK: "8388608"
         run: script -e -c "yarn ccc"
 
       - name: Generate proof data