feat: add HTTP request tool for API interactions

Implements #210 - Add http_request tool that enables the agent to make
HTTP requests to external APIs.

Features:
- Supports GET, POST, PUT, DELETE, PATCH, HEAD, OPTIONS methods
- JSON request/response handling
- Configurable timeout (default: 30s)
- Configurable max response size (default: 1MB)
- Security: domain allowlist, blocks local/private IPs (SSRF protection)
- Headers support with auth token redaction

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/config/schema.rs

@@ -62,6 +62,9 @@ pub struct Config {
     #[serde(default)]
     pub browser: BrowserConfig,
 
+    #[serde(default)]
+    pub http_request: HttpRequestConfig,
+
     #[serde(default)]
     pub identity: IdentityConfig,
 
@@ -272,6 +275,32 @@ pub struct BrowserConfig {
     pub session_name: Option<String>,
 }
 
+// ── HTTP request tool ───────────────────────────────────────────
+
+#[derive(Debug, Clone, Serialize, Deserialize, Default)]
+pub struct HttpRequestConfig {
+    /// Enable `http_request` tool for API interactions
+    #[serde(default)]
+    pub enabled: bool,
+    /// Allowed domains for HTTP requests (exact or subdomain match)
+    #[serde(default)]
+    pub allowed_domains: Vec<String>,
+    /// Maximum response size in bytes (default: 1MB)
+    #[serde(default = "default_http_max_response_size")]
+    pub max_response_size: usize,
+    /// Request timeout in seconds (default: 30)
+    #[serde(default = "default_http_timeout_secs")]
+    pub timeout_secs: u64,
+}
+
+fn default_http_max_response_size() -> usize {
+    1_000_000 // 1MB
+}
+
+fn default_http_timeout_secs() -> u64 {
+    30
+}
+
 // ── Memory ───────────────────────────────────────────────────
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -906,6 +935,7 @@ impl Default for Config {
             composio: ComposioConfig::default(),
             secrets: SecretsConfig::default(),
             browser: BrowserConfig::default(),
+            http_request: HttpRequestConfig::default(),
             identity: IdentityConfig::default(),
             agents: HashMap::new(),
         }
@@ -1257,6 +1287,7 @@ mod tests {
             composio: ComposioConfig::default(),
             secrets: SecretsConfig::default(),
             browser: BrowserConfig::default(),
+            http_request: HttpRequestConfig::default(),
             identity: IdentityConfig::default(),
             agents: HashMap::new(),
         };
@@ -1329,6 +1360,7 @@ default_temperature = 0.7
             composio: ComposioConfig::default(),
             secrets: SecretsConfig::default(),
             browser: BrowserConfig::default(),
+            http_request: HttpRequestConfig::default(),
             identity: IdentityConfig::default(),
             agents: HashMap::new(),
         };