Add security hardening, Ghidra, recreate skill, checkpoints, shells, web search and themes

- Sandbox (bubblewrap) for non-admin shell/git, MCP per-user rights, hard budgets and quotas,
  login rate limiting, audit log and backups
- Ghidra headless decompilation (ARM64 natives built from source), binary_info tool,
  clean room / deep workflow per session
- Recreate skill and commands for analysing and re-building old software
- File checkpoints with rewind/restore, background shells (bash_output, kill_shell)
- web_search tool (DuckDuckGo, SearXNG, Brave, Tavily)
- In-app dialogs and toasts instead of browser dialogs
- 15 base themes (trilium-themes palettes plus Nord, VS Code, GitHub, Catppuccin, One,
  Dracula, Rose Pine, Everforest, Kanagawa) with light/dark/auto switcher and license notes

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

server/src/config.rs

@@ -21,6 +21,38 @@ pub struct Config {
     pub craft: CraftConfig,
     pub auth: AuthConfig,
     pub images: ImagesConfig,
+    pub sandbox: SandboxConfig,
+    pub search: SearchConfig,
+}
+
+/// Web search for the web_search tool.
+#[derive(Debug, Clone, Deserialize, Serialize)]
+#[serde(default)]
+pub struct SearchConfig {
+    /// "duckduckgo" (no key), "searxng", "brave" or "tavily".
+    pub provider: String,
+    /// SearXNG base URL.
+    pub url: String,
+    pub api_key: String,
+}
+
+impl Default for SearchConfig {
+    fn default() -> Self {
+        Self { provider: "duckduckgo".into(), url: String::new(), api_key: String::new() }
+    }
+}
+
+#[derive(Debug, Clone, Deserialize, Serialize)]
+#[serde(default)]
+pub struct SandboxConfig {
+    /// "auto": sandbox shell/git of non-admin users, "always": everybody, "off": nobody.
+    pub mode: String,
+}
+
+impl Default for SandboxConfig {
+    fn default() -> Self {
+        Self { mode: "auto".into() }
+    }
 }
 
 /// Image generation via fal.ai.
@@ -152,6 +184,8 @@ pub struct ServerConfig {
     pub monthly_budget: f64,
     /// Warn when this share of a budget is used (0.0–1.0).
     pub budget_warning: f64,
+    /// "warn" (default) or "block": refuse new model requests once a budget is used up.
+    pub budget_action: String,
 }
 
 impl Default for ServerConfig {
@@ -168,6 +202,7 @@ impl Default for ServerConfig {
             mcp_direct_limit: 15,
             monthly_budget: 0.0,
             budget_warning: 0.8,
+            budget_action: "warn".into(),
         }
     }
 }
@@ -292,6 +327,20 @@ pub struct McpConfig {
     /// "auto" (default), "always" or "on_demand": how the server's tools reach the model.
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub load: Option<String>,
+    /// Who may use this server besides admins: usernames or "*" for everybody.
+    #[serde(default, skip_serializing_if = "Vec::is_empty")]
+    pub users: Vec<String>,
+}
+
+impl Config {
+    /// Whether a session owner may use an MCP server (no owner = legacy/admin).
+    pub fn mcp_allowed(&self, server: &str, user: Option<&crate::store::User>) -> bool {
+        match user {
+            None => true,
+            Some(u) if u.is_admin() => true,
+            Some(u) => self.mcp.get(server).is_some_and(|m| m.users.iter().any(|x| x == "*" || x.eq_ignore_ascii_case(&u.username))),
+        }
+    }
 }
 
 #[derive(Debug, Clone, Copy, Deserialize, Serialize, PartialEq, Eq)]
@@ -533,6 +582,9 @@ pub fn redacted_json(cfg: &Config) -> serde_json::Value {
     if let Some(t) = v.pointer_mut("/images/admin_key") {
         mask(t);
     }
+    if let Some(t) = v.pointer_mut("/search/api_key") {
+        mask(t);
+    }
     v
 }