Integrate OpenRouter for AI-powered code review

Add openrouter-rs dependency, review prompt, and markdown formatting.
Update comment API to accept dynamic body. Adjust devcontainer for
podman compatibility.

.devcontainer/devcontainer.json

@@ -12,18 +12,8 @@
     "containerEnv": {
         "SHELL": "/bin/bash"
     },
-    "customizations": {
-        "vscode": {
-            "extensions": ["rust-lang.rust-analyzer", "tamasfe.even-better-toml", "fill-labs.dependi"],
-            "settings": {
-                "[rust]": {
-                    "editor.defaultFormatter": "rust-lang.rust-analyzer",
-                    "editor.formatOnSave": true
-                }
-            }
-        }
-    },
     "workspaceMount": "source=${localWorkspaceFolder},target=/workspaces/herald,type=bind",
     "workspaceFolder": "/workspaces/herald",
+ 	"runArgs": ["--userns=keep-id", "--security-opt", "label=disable"],
     "appPort": [3000]
 }