docs: document server-side rendering pipeline, response timing middleware, and Telegram pairing API

- Add comprehensive documentation for backend content rendering in AGENTS.md, detailing the new `render_content` and `render_title` Jinja globals built on mistune with media processing, emoji shortcodes, and XSS protection
- Document the `X-Response-Time` header and bottom-left render time indicator in README.md
- Update bot token pricing documentation to clarify fallback vs gateway cost headers
- Add `email_accounts` to soft-delete tables and `idx_users_role` composite index in database schema
- Implement `telegram_pairings` and `telegram_links` table creation with column migration and indexes
- Add `/profile/{username}/telegram` endpoint to docs API with request/unpair actions
- Register `TelegramService` in main.py lifespan and add `response_timing` middleware emitting `X-Response-Time` header
- Introduce `TelegramPairForm` model and `guard_public_host_sync` synchronous host validation function

devplacepy/services/devii/tasks/actions.py

@@ -77,6 +77,13 @@ TASK_ACTIONS: tuple[Action, ...] = (
                 required=True,
             ),
             field("label", "Optional short human-readable label for the task."),
+            field(
+                "notify",
+                "Set true for a REMINDER: when the task fires, the user is sent an in-app "
+                "notification and live toast carrying the result, so it reaches them even when "
+                "the Devii terminal is closed. Leave false for silent background automation.",
+                kind="boolean",
+            ),
             *SCHEDULE_FIELDS,
         ),
     ),
@@ -116,6 +123,11 @@ TASK_ACTIONS: tuple[Action, ...] = (
             field("prompt", "New prompt."),
             field("label", "New label."),
             field("enabled", "Enable or disable the task.", kind="boolean"),
+            field(
+                "notify",
+                "Enable or disable the in-app reminder notification when this task fires.",
+                kind="boolean",
+            ),
             field("kind", "New schedule type when rescheduling."),
             field("run_at", "New absolute run time for kind=once."),
             field("delay_seconds", "New relative delay for kind=once.", kind="integer"),