Add web terminal, git credentials, OpenSCAD, review loops, automations

- Web terminal (PTY over WebSocket, xterm.js, sandboxed, reattach with replay)
- Per-user git credentials and commit identity (credential store in the user's home)
- OpenSCAD tool (STL/3MF + preview renders, bounding box) and cad skill; 3D model card
- Craft phase inferred from tool activity when the agent does not report it
- Configurable review loop per mode (rounds, reviewer model, criteria)
- Delete config and Markdown agents from the agent editor
- Automations: cron-scheduled agents from Markdown job files, schedule tool, page
- change_directory tool (only on the user's request)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

server/src/config.rs

@@ -436,6 +436,24 @@ pub struct AgentConfig {
     /// Max. instances of this subagent running at the same time.
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub max_parallel: Option<usize>,
+    /// Review loop after each turn of this mode.
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub refine: Option<RefineConfig>,
+}
+
+/// Refinement loop: after the agent finishes, a reviewer checks the result
+/// against the request; with findings the agent continues (max. `rounds`).
+#[derive(Debug, Clone, Deserialize, Serialize, Default)]
+pub struct RefineConfig {
+    /// Review rounds per turn (0 = off).
+    #[serde(default)]
+    pub rounds: u32,
+    /// Reviewer model ("provider/model"); empty = the session's model.
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub model: Option<String>,
+    /// Review criteria; empty = the mode's defaults.
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub criteria: Option<String>,
 }
 
 #[derive(Debug, Clone, Deserialize, Serialize)]