fix: resolve TS errors and Svelte 5 state_referenced_locally warnings

- e_app_sign_in_out: type user_id/person_id as string|null (TS errors)
- archives/[archive_id]/+page.svelte: move if(browser) block to onMount
- ae_idaa_comp__archive_obj_id_edit: wrap timezone loader in onMount
- ae_idaa_comp__archive_content_obj_id_edit: wrap timezone loader in onMount
- bb/[post_id]/+page.svelte: move if(browser) block to onMount
- TODO: add completed entries, note remaining recovery_meetings warnings

src/lib/app_components/e_app_sign_in_out.svelte

@@ -43,7 +43,7 @@
     let url_user_email = $state(untrack(() => data?.url?.searchParams?.get('user_email')));
 
     $effect(() => {
-        // NOTE: Sync URL params to state. 
+        // NOTE: Sync URL params to state.
         // We use untrack to prevent infinite loops if navigation triggers within this effect.
         // WARNING: Ensure this doesn't clobber user-entered data during background URL updates.
         untrack(() => {
@@ -57,9 +57,9 @@
     let ae_promises: key_val = {};
 
     let trigger: null | boolean = $state(null); // Use $state to ensure reactivity
-    let user_id = $state(null); // Use $state to ensure reactivity
+    let user_id: string | null = $state(null); // Use $state to ensure reactivity
     let user_obj: key_val = $state({}); // Use $state to ensure reactivity
-    let person_id = $state(null); // Use $state to ensure reactivity
+    let person_id: string | null = $state(null); // Use $state to ensure reactivity
     let person_obj: key_val = $state({}); // Use $state to ensure reactivity
 
     $effect(() => {