feat(notify): add notif to internal users when granted

- add coalesced protection to avoid mail bombing if an invited goes many grant in a short period
    - add resentd method in share menu item (work for both internal and external users)
    - user can disable email notification via his properties
    - add env variable from admin to disable notifications

static/locales/en.json

@@ -30,12 +30,28 @@
                 "kind_folder": "folder",
                 "english_fallback_divider": "--- English version below ---"
             }
+        },
+        "notification": {
+            "share": {
+                "subject": "{{inviter}} shared a {{kind}} with you on OxiCloud",
+                "body": "{{inviter}} shared a {{kind}} with you on OxiCloud.\n\nOpen OxiCloud to see your new share:\n{{login_link}}\n\nYou may have additional new shares from {{inviter}} — sign in to see all your shared items.\n\n— OxiCloud\n\nYou're receiving this message because you have an OxiCloud account and your share-notification preference is on. You can turn it off in your profile (Email me when someone shares with me)."
+            }
         }
     },
     "app": {
         "title": "OxiCloud",
         "description": "Minimalist cloud storage system"
     },
+    "myshares": {
+        "resendInvitation": "Resend invitation email",
+        "notifyByEmail": "Notify by email",
+        "notifyGroupMembers": "Notify group members",
+        "notifyRateLimited": "Too many notifications for this recipient — try again later.",
+        "notifyFailed": "Could not send notification.",
+        "removeAccess": "Remove access",
+        "copyLink": "Copy link",
+        "deleteLink": "Delete link"
+    },
     "nav": {
         "files": "Files",
         "shared": "My shares",
@@ -759,6 +775,8 @@
         "username_already_claimed": "Username is set and can't be changed (DAV/NextCloud clients depend on it).",
         "given_name": "First name",
         "family_name": "Last name",
+        "notify_on_share": "Email me when someone shares with me",
+        "notify_on_share_hint": "When unchecked, shares still appear in your account — you just won't get an email about them.",
         "save_profile": "Save changes",
         "profile_saved": "Profile updated",
         "profile_no_changes": "No changes to save.",