fix(state): add memory cleanup for allocated State fields

- Add deinit() method to State struct to free session_id and last_update
- Call st.deinit() in main.zig before program exit
- Fixes memory leak when State is loaded from JSON file

The State.load() function allocates memory for session_id and last_update
using allocator.dupe(), but this memory was never freed. This commit adds
proper cleanup to prevent memory leaks.

Signed-off-by: leocavalcante <[email protected]>

Author: leocavalcante

src/main.zig

@@ -112,6 +112,9 @@ fn runOpencoder(cfg: config.Config, allocator: std.mem.Allocator) !void {
         log.logErrorFmt("Failed to save final state: {}", .{err});
     };
 
+    // Clean up state
+    st.deinit(allocator);
+
     log.say("");
     log.say("Opencoder stopped");
 }

src/state.zig

@@ -58,6 +58,16 @@ pub const State = struct {
         return State{};
     }
 
+    /// Free allocated memory for state fields
+    pub fn deinit(self: *State, allocator: Allocator) void {
+        if (self.session_id) |sid| {
+            allocator.free(sid);
+        }
+        if (self.last_update.len > 0) {
+            allocator.free(self.last_update);
+        }
+    }
+
     /// Save state to JSON file
     pub fn save(self: *const State, path: []const u8, allocator: Allocator) !void {
         // Generate current timestamp