Add integration examples

Show how to wire the proxy into docker-compose and devcontainer setups without guessing the required mounts and commands.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

examples/devcontainer.json

@@ -0,0 +1,10 @@
+{
+  "name": "app-with-host-git-cred-proxy",
+  "image": "mcr.microsoft.com/devcontainers/base:ubuntu",
+  "workspaceFolder": "/workspace",
+  "workspaceMount": "source=${localWorkspaceFolder},target=/workspace,type=bind,consistency=cached",
+  "mounts": [
+    "source=${localEnv:HOST_GIT_CRED_PROXY_DIR},target=/opt/host-git-cred-proxy,type=bind,readonly"
+  ],
+  "postCreateCommand": "/opt/host-git-cred-proxy/container/configure-git.sh --global"
+}

examples/docker-compose.yml

@@ -0,0 +1,16 @@
+services:
+  dev:
+    image: mcr.microsoft.com/devcontainers/base:ubuntu
+    working_dir: /workspace
+    command: >
+      bash -lc "
+        /opt/host-git-cred-proxy/container/configure-git.sh --global &&
+        sleep infinity
+      "
+    tty: true
+    stdin_open: true
+    environment:
+      GIT_CRED_PROXY_URL: ${GIT_CRED_PROXY_URL:-http://host.docker.internal:18765}
+    volumes:
+      - .:/workspace
+      - ${HOST_GIT_CRED_PROXY_DIR}:/opt/host-git-cred-proxy:ro