refactor: move sandbox files into .flue/sandbox/ directory

Author: FredKSchott

.flue/AGENTS.sandbox.md .flue/sandbox/AGENTS.md.flue/AGENTS.sandbox.md renamed to .flue/sandbox/AGENTS.md

@@ -65,7 +65,7 @@ RUN git config --system --add safe.directory '*'
 # --- Global OpenCode rules for CI sessions ---
 # The flue CLI sets HOME=/tmp at runtime, so OpenCode reads global rules from
 # /tmp/.config/opencode/AGENTS.md. This injects CI-specific instructions.
-COPY .flue/AGENTS.sandbox.md /tmp/.config/opencode/AGENTS.md
+COPY .flue/sandbox/AGENTS.md /tmp/.config/opencode/AGENTS.md
 
 EXPOSE 48765
 

.flue/Dockerfile.sandbox .flue/sandbox/Dockerfile.flue/Dockerfile.sandbox renamed to .flue/sandbox/Dockerfile

@@ -2,7 +2,7 @@ name: Build Sandbox Image
 
 on:
   push:
-    paths: ['.flue/Dockerfile.sandbox', '.flue/AGENTS.sandbox.md', '.github/workflows/build-sandbox-image.yml']
+    paths: ['.flue/sandbox/Dockerfile', '.flue/sandbox/AGENTS.md', '.github/workflows/build-sandbox-image.yml']
   workflow_dispatch:
 
 env:
@@ -31,10 +31,10 @@ jobs:
       - uses: docker/build-push-action@10e90e3645eae34f1e60eeb005ba3a3d33f178e8 # v6.19.2
         with:
           context: .
-          file: .flue/Dockerfile.sandbox
+          file: .flue/sandbox/Dockerfile
           push: true
           tags: |
             ${{ env.IMAGE }}:latest
-            ${{ env.IMAGE }}:${{ hashFiles('.flue/Dockerfile.sandbox', '.flue/AGENTS.sandbox.md') }}
+            ${{ env.IMAGE }}:${{ hashFiles('.flue/sandbox/Dockerfile', '.flue/sandbox/AGENTS.md') }}
           cache-from: type=gha
           cache-to: type=gha,mode=max