Started adding the reference system to add images

by adding a hash to each photo and also the possibility to add a reference by pressing i whilst the sidebar is on focus

src/pilgrim/ui/screens/modals/add_photo_modal.py

@@ -5,6 +5,7 @@ from textual.screen import Screen
 from textual.widgets import Static, Input, Button
 from textual.containers import Horizontal, Container
 from .file_picker_modal import FilePickerModal
+import hashlib
 
 class AddPhotoModal(Screen):
     """Modal for adding a new photo"""
@@ -12,6 +13,14 @@ class AddPhotoModal(Screen):
         super().__init__()
         self.diary_id = diary_id
         self.result = None
+        self.created_photo = None
+
+    def _generate_photo_hash(self, photo_data: dict) -> str:
+        """Generate a short, unique hash for a photo"""
+        # Use temporary data for hash generation
+        unique_string = f"{photo_data['name']}_{photo_data.get('photo_id', 0)}_new"
+        hash_object = hashlib.md5(unique_string.encode())
+        return hash_object.hexdigest()[:8]
 
     def compose(self) -> ComposeResult:
         yield Container(
@@ -72,13 +81,23 @@ class AddPhotoModal(Screen):
             )
 
             if new_photo:
-                self.notify(f"Photo '{new_photo.name}' added successfully!")
+                self.created_photo = new_photo
+                # Generate hash for the new photo
+                photo_hash = self._generate_photo_hash({
+                    "name": new_photo.name,
+                    "photo_id": new_photo.id
+                })
+                
+                self.notify(f"Photo '{new_photo.name}' added successfully!\nHash: {photo_hash}\nReference: \\[\\[photo:{new_photo.name}:{photo_hash}\\]\\]", 
+                           severity="information", timeout=5)
+                
                 # Return the created photo data to the calling screen
                 self.result = {
                     "filepath": photo_data["filepath"],
                     "name": photo_data["name"],
                     "caption": photo_data["caption"],
-                    "photo_id": new_photo.id
+                    "photo_id": new_photo.id,
+                    "hash": photo_hash
                 }
                 self.dismiss(self.result)
             else: