feat: scaffold element_ae_obj_field_editor_new — parallel-run rewrite of inline field editor

Creates the _new version of the field editor element alongside the working
original (which remains untouched). The _new file starts from the original's
hardened optimistic-update state machine and adds:

- Svelte 5 generics (T) on current_value/draft_value instead of any
- email / url / tel added to the field_type union with edit-mode branches
- object_reload prop removed (was declared, never implemented — on_success
  is and remains the caller's cache-refresh hook)
- to_input_value() / from_input_value() stubs at the two right call sites
  for datetime conversion (both directions, TODO #4 to implement)
- coerce_select_value() stub for select type-mismatch fix (TODO #5)
- Inline TODO mini how-to checked-list mirroring the project doc
- Styling still uses Skeleton classes — tagged for Tailwind/Flowbite swap
  (TODO #6) and a11y gaps marked at their exact markup locations (TODO #7)

Companion files:
- documentation/PROJECT__AE_Obj_Field_Editor_New.md — full plan, migration
  order for all 8 call sites, naming convention note
- documentation/TODO__Agents.md — new entry pointing to the project doc
- documentation/README__Docs_Index.md — project doc added to Active Projects

npx svelte-check: 0 errors, 1 expected benign warning (state_referenced_locally
on the field_type initializer, documented in-file).

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

documentation/README__Docs_Index.md

@@ -55,6 +55,7 @@ Use this file as the routing map for project documentation.
 - `documentation/PROJECT__IDAA_Stores_Svelte5_Migration_2026.md`
 - `documentation/PROJECT__AE_Events_PressMgmt_Config_Cleanup.md`
 - `documentation/PROJECT__AE_Site_Passcode_Security.md`
+- `documentation/PROJECT__AE_Obj_Field_Editor_New.md`
 
 ## 6) Active Proposals