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

documentation/TODO__Agents.md

@@ -41,6 +41,8 @@ lead record look like in the DB?
 - **Input Field Audit:** Several input fields are missing `name`/`id` attributes or `data-testid`. Known examples: badge override fields in `ae_comp__badge_obj_view.svelte`; template name input in `ae_comp__badge_template_form.svelte`. Matters for: accessibility, autofill, label associations, and test targeting. (For tests, use `getByLabel()` rather than `input[value*=...]` which only checks the HTML attribute, not the Svelte-bound DOM property.)
 
 ## ✅ Completed Recently
+- [x] **[Svelte]** **`state_referenced_locally` warning fixes (2026-03-09):** Resolved 10 Svelte 5 warnings where `$state`/`$props()` variables were read in top-level synchronous script code instead of inside a reactive closure. Fixed by moving `if (browser) { ... }` blocks and timezone-loading blocks into `onMount`. Files: `archives/[archive_id]/+page.svelte`, `archives/[archive_id]/ae_idaa_comp__archive_obj_id_edit.svelte`, `archives/[archive_id]/ae_idaa_comp__archive_content_obj_id_edit.svelte`, `bb/[post_id]/+page.svelte`. Note: 42 similar warnings remain in `recovery_meetings/ae_idaa_comp__event_obj_id_edit.svelte` and `..._v2.svelte` — same pattern, fix next session.
+- [x] **[TypeScript]** **Sign In/Out TS errors fixed (2026-03-09):** `user_id` and `person_id` in `e_app_sign_in_out.svelte` were implicitly typed `null` from `$state(null)`, causing assignment errors. Explicitly typed as `string | null`.
 - [x] **[UI]** **Firefly Theme:** Created `AE_Firefly` dark/light theme. Primary=teal (~184°), Secondary=amber (~90°), Tertiary=indigo (~277°), Surface=moonlit slate. Files: `src/ae-firefly.css`, `src/app.css`, `src/lib/elements/e_app_theme.svelte`, `src/lib/ae_core/ae_stores.ts`. Set as app default in stores. (2026-03-06, branch `ae_app_3x_llm`)
 - [x] **[UI]** **Pres Mgmt Visual Redesign:** Full redesign of Events Presentation Management pages using Firefly theme tokens. Hero card layout, info chips (time=teal, room=indigo), skeleton loading states, dark-mode-safe colors throughout. 5 files: `session_view.svelte`, `ae_comp__event_session_obj_li.svelte`, `ae_comp__event_presentation_obj_li.svelte`, `pres_mgmt/+page.svelte`, `[session_id]/+page.svelte`. (2026-03-06, branch `ae_app_3x_llm`)
 - [x] **[Docs]** **UI Design System Docs:** Created two cheatsheet/reference docs: `documentation/GUIDE__AE_UI_Style_Guidelines.md` (design philosophy, color token rules, forbidden classes, Skeleton v3→v4 migration table, transitions, dark mode rules, a11y checklist) and `documentation/AE__UI_Component_Patterns.md` (hero cards, content cards, table rows, list item cards, info chips, empty state panels, warning/error banners, file upload zones, section wrappers, modals, muted text, QR code pattern). (2026-03-06)