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.

src/consts.rs

@@ -1,3 +1,36 @@
 pub const GITEA_SIG_HEADER_NAME: &str = "x-gitea-signature";
 pub const GITEA_EVENT_TYPE_HEADER_NAME: &str = "x-gitea-event-type";
 pub const MAX_WEBHOOK_BODY_SIZE: usize = 1024 * 1024; // 1 MiB
+
+pub const BOT_PROCESS_MSG: &str = "
+    Review in progress with the model \"{model}\"...
+";
+
+pub const REVIEW_PROMPT: &str = "
+    You are a senior software engineer reviewing code changes.
+
+    Check good practices and code quality.
+
+    This is the pull request subject: \"{subject}\"
+
+    This is the user comment: \"{comment}\"
+
+    This is the git diff of the code changes:
+
+    \"{diff}\"
+
+    Please review the code changes and provide feedback.
+    Return your feedback with only this json format, reviews must contain each review (filename field must contain the full path with extension) and comment msut contain a final summary:
+
+    {
+        \"reviews\": [
+            {
+                \"filename\": \"\",
+                \"line\": ,
+                \"code\": \"\",
+                \"message\": \"\"
+            }
+        ],
+        \"comment\": \"\"
+    }
+";