docs: document build_tmp_sort pattern and liveQuery filter dependency capture

Added two new sections to GUIDE__SvelteKit2_Svelte5_DexieJS.md:
- IDB Sort: build_tmp_sort Pattern — sort chain, priority inversion
  encoding, anti-.reverse() warning, modules using it
- $derived.by Dependency Capture — SCENARIO 2 filter pattern and
  API snapshot consistency fix

Updated TODO__Agents.md:
- Added anti-.reverse() warning and guide pointer to build_tmp_sort entry
- Added Sessions hide/show toggle section with both fixes marked complete

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

documentation/TODO__Agents.md

@@ -57,6 +57,8 @@ The app uses `svelte-persisted-store` (coarse reactivity). Migration target: rep
 Shared utility in `src/lib/ae_core/core__idb_sort.ts` — fixes priority direction (inverted,
 true→'0' sorts first ASC) and zero-pads sort field (8 chars). No `.reverse()` needed.
 Sort chain: `group → priority DESC → sort ASC → [module-specific fields] → name`.
+**⚠️ Never use `.reverse()` on a `tmp_sort_*`-sorted list — inverted priority makes it wrong.**
+Documented in `GUIDE__SvelteKit2_Svelte5_DexieJS.md` (IDB Sort section).
 
 - [x] `ae_events__event_presentation` — group + priority + sort + start_datetime + code + name
 - [x] `ae_journals__journal` + `ae_journals__journal_entry` — group + priority + sort + name + updated_on
@@ -82,6 +84,22 @@ Sort chain: `group → priority DESC → sort ASC → [module-specific fields]
 
 ---
 
+### [Pres Mgmt] Sessions hide/show toggle
+- [x] **[Pres Mgmt] Hidden sessions blink on initial load** — SCENARIO 2 fallback in
+  `pres_mgmt/+page.svelte` now captures `qry_hidden` as a `$derived.by` dependency and
+  applies the filter in the fallback path. No blink on page load. (2026-05-28)
+- [x] **[Pres Mgmt] API call uses live store instead of snapshot** — changed
+  `pres_mgmt_loc.current.qry_hidden` → `params.qry_hidden` in `handle_search_refresh`
+  API call to be consistent with fast path snapshot. (2026-05-28)
+- **Note:** `hide_event_launcher` is still active — used in `menu_session_list.svelte`
+  (Launcher) to CSS-hide sessions from the list. Button to toggle it is in
+  `session_page_menu.svelte`. Not used in Pres Mgmt (intentional — Pres Mgmt always shows all).
+- **Note:** Non-trusted users always have `!item.hide` applied at the component level
+  in `ae_comp__event_session_obj_li.svelte` regardless of `qry_hidden`. Toggle is
+  trusted-access-only in practice; direct session links still work for non-trusted users.
+
+---
+
 ## 🧪 Testing & Optimization
 
 - [ ] **[IDAA] IDB fast-path contact search** — parse `contact_li_json` in `search__event()`.