fix(core): resolve 68 compiler errors and stabilize Svelte 5 reactivity

- Fixed 'Captured initial value' warnings in 65+ components by implementing
  proper sync effects with 'untrack' and derived states.
- Hardened Event Settings JSON editors using a temporary string-buffer pattern
  to safely decouple object-based data from CodeMirror's string requirements.
- Resolved strict TypeScript mismatches across core routes (Accounts, Sites, etc.)
  and improved property indexing safety in views.
- Patched Flowbite-Svelte Drawer transitions for Svelte 5 compatibility using
  prop spreading.
- Added comprehensive safety comments to high-risk reactivity blocks.
- Synchronized 'ae_types.ts' with V3 backend models.

src/routes/events/[event_id]/sign_in_out.svelte

@@ -230,7 +230,7 @@
                     placeholder="Key"
                     value={$events_sess.auth__entered_key ?? ''}
                     oninput={(e) =>
-                        ($events_sess.auth__entered_key = e.target?.value)}
+                        ($events_sess.auth__entered_key = (e.target as HTMLInputElement).value)}
                 />
                 <input
                     type="text"
@@ -238,7 +238,7 @@
                     placeholder="Passcode"
                     value={$events_sess.auth__entered_passcode ?? ''}
                     oninput={(e) =>
-                        ($events_sess.auth__entered_passcode = e.target?.value)}
+                        ($events_sess.auth__entered_passcode = (e.target as HTMLInputElement).value)}
                 />
                 <button
                     type="button"