feat: replaced ollama with litellm (#18)

Co-authored-by: Sharang Parnerkar <parnerkarsharang@gmail.com>
Reviewed-on: https://gitea.meghsakha.com/sharang/certifai/pulls/18

src/models/chat.rs

@@ -60,8 +60,8 @@ pub struct Attachment {
 /// * `user_sub` - Keycloak subject ID (session owner)
 /// * `title` - Display title (auto-generated or user-renamed)
 /// * `namespace` - Grouping for sidebar sections
-/// * `provider` - LLM provider used (e.g. "ollama", "openai")
-/// * `model` - Model ID used (e.g. "llama3.1:8b")
+/// * `provider` - LLM provider used (e.g. "litellm", "openai")
+/// * `model` - Model ID used (e.g. "qwen3-32b")
 /// * `created_at` - ISO 8601 creation timestamp
 /// * `updated_at` - ISO 8601 last-activity timestamp
 /// * `article_url` - Source article URL (for News namespace sessions)
@@ -171,8 +171,8 @@ mod tests {
             user_sub: "user-1".into(),
             title: "Test Chat".into(),
             namespace: ChatNamespace::General,
-            provider: "ollama".into(),
-            model: "llama3.1:8b".into(),
+            provider: "litellm".into(),
+            model: "qwen3-32b".into(),
             created_at: "2025-01-01T00:00:00Z".into(),
             updated_at: "2025-01-01T01:00:00Z".into(),
             article_url: None,
@@ -189,7 +189,7 @@ mod tests {
             "_id": "mongo-id",
             "user_sub": "u1",
             "title": "t",
-            "provider": "ollama",
+            "provider": "litellm",
             "model": "m",
             "created_at": "2025-01-01",
             "updated_at": "2025-01-01"
@@ -205,7 +205,7 @@ mod tests {
             user_sub: "u1".into(),
             title: "t".into(),
             namespace: ChatNamespace::default(),
-            provider: "ollama".into(),
+            provider: "litellm".into(),
             model: "m".into(),
             created_at: "2025-01-01".into(),
             updated_at: "2025-01-01".into(),
@@ -223,7 +223,7 @@ mod tests {
             user_sub: "u1".into(),
             title: "t".into(),
             namespace: ChatNamespace::default(),
-            provider: "ollama".into(),
+            provider: "litellm".into(),
             model: "m".into(),
             created_at: "2025-01-01".into(),
             updated_at: "2025-01-01".into(),