feat: implement Trello list management

Add 4 list management tools extending the Trello client:
- trello_create_list — create a new list on a board
- trello_rename_list — rename an existing list
- trello_archive_list — archive a list
- trello_move_list — move a list to a new position

Also update the auth spec doc to reflect the PR #5 review fixes
(TypedDict contracts, updated disconnect message).

Issue: #3

docs/backend/manage-lists-spec.md

@@ -0,0 +1,88 @@
+# Trello Plugin — Manage Trello Lists
+
+**Feature:** US: Manage Trello Lists
+**Issue:** #3
+**Branch:** `feature/manage-lists`
+
+## Overview
+
+Extends the Trello plugin with list management capabilities: create, rename, archive, and reposition lists on a Trello board.
+
+## Design Decisions
+
+- **Lists require a board context** — Creating a list needs a board ID. Other operations (rename, archive, move) use the list's Trello ID which is globally unique.
+- **Position parameter** — Uses Trello's `pos` field which accepts `"top"`, `"bottom"`, or a positive number.
+
+## Tools
+
+### `trello_create_list`
+
+Create a new list on a board.
+
+**Parameters:**
+| Param | Type | Required | Description |
+|-------|------|----------|-------------|
+| `name` | string | Yes | List name |
+| `board_id` | string | Yes | Board ID or name |
+| `pos` | string | No | Position: `"top"`, `"bottom"`, or number (default: `"bottom"`) |
+
+**Returns:**
+```json
+{"success": true, "list": {"id": "l1", "name": "My List", "id_board": "b1"}}
+```
+
+### `trello_rename_list`
+
+Rename an existing list.
+
+**Parameters:**
+| Param | Type | Required | Description |
+|-------|------|----------|-------------|
+| `list_id` | string | Yes | List ID |
+| `name` | string | Yes | New name |
+
+**Returns:**
+```json
+{"success": true, "list": {"id": "l1", "name": "Renamed List"}}
+```
+
+### `trello_archive_list`
+
+Archive a list.
+
+**Parameters:**
+| Param | Type | Required | Description |
+|-------|------|----------|-------------|
+| `list_id` | string | Yes | List ID |
+
+**Returns:**
+```json
+{"success": true, "message": "List 'My List' archived."}
+```
+
+### `trello_move_list`
+
+Move a list to a different position.
+
+**Parameters:**
+| Param | Type | Required | Description |
+|-------|------|----------|-------------|
+| `list_id` | string | Yes | List ID |
+| `pos` | string | Yes | Position: `"top"`, `"bottom"`, or a number |
+
+**Returns:**
+```json
+{"success": true, "message": "List 'My List' moved."}
+```
+
+## Trello API Endpoints
+
+| Purpose | Method | Endpoint |
+|---------|--------|----------|
+| Create list | POST | `/1/lists` |
+| Update list (rename, archive, move) | PUT | `/1/lists/{id}` |
+
+## Error Handling
+
+- List not found → clear error message
+- Board not found when creating → propagate board lookup error

docs/backend/trello-auth-spec.md

@@ -64,7 +64,9 @@ Fetches and returns all Trello boards accessible to the authenticated user.
 
 ### 3. `trello_disconnect`
 
-Clears the stored credentials from memory. Note: this does not revoke the Trello token — the user must invalidate it via Trello's settings if needed.
+Clears the stored credentials from memory. Since credentials are stored in environment variables, the next tool call will automatically re-read them and reconnect. To fully disconnect, also unset ``TRELLO_API_KEY`` and ``TRELLO_TOKEN`` from the Hermes profile config.
+
+Note: this does NOT revoke the Trello token — the user must invalidate it via Trello's settings if needed.
 
 **Parameters:** None
 
@@ -72,7 +74,7 @@ Clears the stored credentials from memory. Note: this does not revoke the Trello
 ```json
 {
   "success": true,
-  "message": "Trello credentials cleared. Set TRELLO_API_KEY and TRELLO_TOKEN again to reconnect."
+  "message": "Trello credentials cleared from memory. Next tool call will re-read TRELLO_API_KEY and TRELLO_TOKEN from environment and reconnect automatically."
 }
 ```
 
@@ -82,6 +84,9 @@ Clears the stored credentials from memory. Note: this does not revoke the Trello
 
 ```python
 class TrelloClient:
+    api_key: str
+    token: str
+
     def __init__(self, api_key: str | None = None, token: str | None = None)
 
     def verify_credentials(self) -> dict
@@ -89,6 +94,8 @@ class TrelloClient:
     def disconnect(self) -> dict
 ```
 
+The client uses `TypedDict` response contracts (`SuccessResponse`/`ErrorResponse`) with a `TypeGuard` helper `_is_success()` for type-safe narrowing. Internal helpers include `_request()`, `_get()`, `_post()`, `_put()`, `_check_credentials()`, and `_handle_http_error()`.
+
 ### Trello API Endpoints Used
 
 | Purpose | Method | Endpoint | Docs |