feat(acp): bridge durable image prompts and replies

examples/acp-agent/code-mode-image.cordis.yml

@@ -0,0 +1,29 @@
+# Code Mode image overlay: mounts the worker runtime and durable attachment
+# store so a nested read_image result can cross the generic rich-result bridge.
+# The authored snapshot is replay-only; the live config retains the ordinary
+# exact provider route for manual use.
+- id: base
+  name: '@deepseek-ai/cordis-plugin-include'
+  config:
+    path: ./cordis.yml
+    patches:
+      - id: acp-agent
+        name: '@deepseek-ai/dsh-acp-demo'
+        config:
+          provider: deepseek-official
+          model: deepseek-v4-pro
+          persistenceRoot: !!js process.env.DSH_SNAPSHOT_SESSIONS_ROOT ?? './.sessions'
+          persistenceCompression: !!js "process.env.DSH_SNAPSHOT === undefined ? 'zstd' : 'none'"
+          workspaceContext:
+            maxBytes: 65536
+          tools:
+            mode: code
+          persona: |
+            You are a coding assistant powered by the {{model}} model. Your working directory is {{cwd}}.
+
+            Verify your work by running the code or tests. Keep answers brief and factual.
+      - insert:
+          - id: attachment-local
+            name: '@deepseek-ai/dsh-attachment-local'
+          - id: code-runtime
+            name: '@deepseek-ai/dsh-code-runtime-worker'