feat(journals): extract decryption logic to helper and improve Quick Add behavior

- Extracted journal entry decryption workflow to 'ae_journals_decryption.ts' to decouple it from Svelte reactivity and address loop issues.
- Updated 'ae_comp__journal_entry_obj_id_view.svelte' to use the new decryption helper.
- Refactored 'Quick Add' to use the first line as the title and remove it from the content before saving.

documentation/V3_FRONTEND_API_GUIDE.md

@@ -188,3 +188,49 @@ const downloadUrl = `${BASE_URL}/v3/crud/hosted_file/${fileId}/?jwt=${jwtToken}`
 1.  **Use `view` for Rich Data**: Instead of manually joining data in separate calls, use `?view=enriched` or `?view=detail`.
 2.  **Singular Nouns**: Always use singular names for `obj_type` (e.g., `journal`).
 3.  **Strict Typing**: Ensure your `data` objects match the backend models to avoid `400 Bad Request` validation errors.
+
+---
+
+## 8. Standard Patterns & Common Pitfalls (2026 Update)
+
+To ensure stability across the Aether mesh, all frontend components must adhere to these established patterns.
+
+### A. The "Whitelist" Standard for Saves
+**Problem:** Sending the entire object returned by a `GET` request back to a `PATCH` endpoint will cause a `400 Bad Request`. This happens because the object contains technical metadata (like `journal_id`, `created_on`, `for_type`) that the API cannot "SET".
+
+**Standard:** When preparing a save payload, explicitly whitelist ONLY the user-editable fields.
+```typescript
+// ✅ CORRECT: Whitelist only editable fields
+const data_kv = {
+    name: tmp_obj.name,
+    content: tmp_obj.content,
+    tags: tmp_obj.tags,
+    category_code: tmp_obj.category_code
+};
+
+// ❌ WRONG: Passing the whole object or just blacklisting a few
+const data_kv = { ...tmp_obj }; 
+delete data_kv.id; // Still contains other computed columns!
+```
+
+### B. The Triple-ID Save Pattern
+**Standard:** When sending an ID in a POST/PATCH payload (e.g. creating a child object), use the random string version with the `_id_random` suffix.
+*   **Property:** `[obj_type]_id_random`
+*   **Value:** A string (e.g., `qpgvOh5nOYI`)
+
+**Warning:** Sending a string value under an integer key (e.g. `journal_id: "qpgvOh5nOYI"`) will trigger a Pydantic validation error on the backend.
+
+### C. Handle 'NULL' vs '0' for Booleans
+**Pitfall:** Fields like `hide` or `priority` can be `NULL` in the database. 
+**Standard:** Ensure your synchronization logic in components handles `null`, `undefined`, and `0` identically for boolean checks to prevent "ghost" changes being detected by Svelte 5.
+
+---
+
+## 9. Planned API Improvements (2026 Roadmap)
+
+The following refinements have been requested from the Backend Agent to further improve frontend productivity:
+
+1.  **Permissive Update Mode**: A new header (`x-ae-ignore-extra-fields: true`) is planned to allow the API to ignore non-writable columns in `PATCH` requests instead of returning a `400 Bad Request`.
+2.  **Automated ID Resolution**: Backend will soon support automatic resolution of `_id_random` strings to integer IDs during `POST/PATCH`, reducing the need for manual lookups in the frontend.
+3.  **Schema Evolution Tools**: New orchestration tools are being developed to automate field creation and renaming, including the automatic regeneration of the enriched SQL views.
+4.  **Structured Validation Errors**: Move from string-based error details to a machine-readable format for better inline form validation.