feat(ollama): enforce JSON logits & add nvim_buffer edit action

- Added format parameter to Ollama generate for JSON logit enforcement.

- Implemented safe edit action in nvim_buffer MCP tool to replace raw Lua.

server/src/handlers/graph.rs

@@ -824,7 +824,7 @@ impl McpTool for CondenseEntityHandler {
                     req.entity_name,
                     unique_obs.join("\n- ")
                 );
-                if let Ok(summary) = state.ollama.generate(&prompt, None, None).await {
+                if let Ok(summary) = state.ollama.generate(&prompt, None, None, None).await {
                     let lines: Vec<String> = summary
                         .lines()
                         .map(|l| l.trim().trim_start_matches('-').trim().to_string())