Add Auto permission mode (#63)

Adds Claude Code's auto permission mode as a fifth option between Accept Edits and Bypass, across terminals, resumed sessions, the tab badge, the scheduler task runner and docs. Warns that Auto falls back to prompting when unavailable for the model/backend.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

HOW-TO-USE.md

@@ -469,6 +469,7 @@ replaces the old Full Permissions on/off switch.
 | **Plan** | Proposes a plan and makes no changes | `--permission-mode plan` |
 | **Default** | Asks before each tool call | *(nothing — Claude Code's own default)* |
 | **Accept Edits** | Auto-approves file edits; other tools still prompt | `--permission-mode acceptEdits` |
+| **Auto** | A safety classifier approves routine actions and blocks risky ones, without prompting | `--permission-mode auto` |
 | **Bypass** | Auto-approves every tool call | `--dangerously-skip-permissions` |
 
 New projects start in **Default**. Projects created before permission modes existed keep behaving
@@ -480,12 +481,19 @@ the way they did: one that had Full Permissions on becomes **Bypass**, one that
 > has Docker socket access or reaches services on your network. The Overview tab tells you whether
 > the in-container sandbox is also on.
 
+**Auto** sits between Accept Edits and Bypass: Claude Code's own classifier reviews each action,
+lets routine work through and blocks things that look risky (such as destructive or
+exfiltrating commands) — no prompts either way. Whether it is available depends on your Claude
+Code account, model and backend (local and OpenAI-compatible backends usually won't
+qualify). When it isn't available, Claude Code quietly starts in its normal prompting mode
+instead.
+
 ### When a change takes effect
 
 - **Terminals** — the mode is applied when a terminal is opened, so it affects terminals you open
   from then on. A Claude session that is already running keeps the permissions it started with;
   close the tab and open a new terminal to change it. The badge on each terminal tab shows the mode
-  that terminal was launched with (`plan`, `ask`, `edits`, `bypass`).
+  that terminal was launched with (`plan`, `ask`, `edits`, `auto`, `bypass`).
 - **Resumed sessions** — a session resumed from the **Sessions** tab uses the project's current
   mode.
 - **Scheduled tasks** — these now honour the permission mode too (they previously always ran with
@@ -494,8 +502,10 @@ the way they did: one that had Full Permissions on becomes **Bypass**, one that
   mode change to reach the scheduler.
 
 > Scheduled tasks run headless (`claude -p`) and cannot answer a permission prompt. In any mode
-> other than **Bypass**, a task may simply stop early when Claude Code asks for approval. Its run
-> log records which mode it used.
+> other than **Auto** or **Bypass**, a task may simply stop early when Claude Code asks for
+> approval. In **Auto**, actions the classifier blocks are denied and the run carries on without
+> them — but if Auto isn't available for the project's model or backend, Claude Code falls back
+> to prompting and the task can stall the same way. Its run log records which mode it used.
 
 ---
 
@@ -1349,7 +1359,9 @@ Scheduled runs use the project's [permission mode](#permission-modes) — they n
 with `--dangerously-skip-permissions`. Because the mode travels into the container as an
 environment variable, **stop and start the project** after changing it for the scheduler to see the
 change. Remember that a headless run cannot answer a permission prompt, so in any mode other than
-**Bypass** a task may stop early when Claude Code asks for approval; the run log records the mode
+**Auto** or **Bypass** a task may stop early when Claude Code asks for approval (in Auto, blocked
+actions are denied instead, unless Auto is unavailable and Claude Code falls back to
+prompting); the run log records the mode
 that was used.
 
 ### Creating Tasks