feat: add multimodal image marker support with Ollama vision

src/config/schema.rs

@@ -124,6 +124,9 @@ pub struct Config {
     #[serde(default)]
     pub http_request: HttpRequestConfig,
 
+    #[serde(default)]
+    pub multimodal: MultimodalConfig,
+
     #[serde(default)]
     pub web_search: WebSearchConfig,
 
@@ -284,6 +287,46 @@ impl Default for AgentConfig {
     }
 }
 
+#[derive(Debug, Clone, Serialize, Deserialize, JsonSchema)]
+pub struct MultimodalConfig {
+    /// Maximum number of image attachments accepted per request.
+    #[serde(default = "default_multimodal_max_images")]
+    pub max_images: usize,
+    /// Maximum image payload size in MiB before base64 encoding.
+    #[serde(default = "default_multimodal_max_image_size_mb")]
+    pub max_image_size_mb: usize,
+    /// Allow fetching remote image URLs (http/https). Disabled by default.
+    #[serde(default)]
+    pub allow_remote_fetch: bool,
+}
+
+fn default_multimodal_max_images() -> usize {
+    4
+}
+
+fn default_multimodal_max_image_size_mb() -> usize {
+    5
+}
+
+impl MultimodalConfig {
+    /// Clamp configured values to safe runtime bounds.
+    pub fn effective_limits(&self) -> (usize, usize) {
+        let max_images = self.max_images.clamp(1, 16);
+        let max_image_size_mb = self.max_image_size_mb.clamp(1, 20);
+        (max_images, max_image_size_mb)
+    }
+}
+
+impl Default for MultimodalConfig {
+    fn default() -> Self {
+        Self {
+            max_images: default_multimodal_max_images(),
+            max_image_size_mb: default_multimodal_max_image_size_mb(),
+            allow_remote_fetch: false,
+        }
+    }
+}
+
 // ── Identity (AIEOS / OpenClaw format) ──────────────────────────
 
 #[derive(Debug, Clone, Serialize, Deserialize, JsonSchema)]
@@ -2534,6 +2577,7 @@ impl Default for Config {
             secrets: SecretsConfig::default(),
             browser: BrowserConfig::default(),
             http_request: HttpRequestConfig::default(),
+            multimodal: MultimodalConfig::default(),
             web_search: WebSearchConfig::default(),
             proxy: ProxyConfig::default(),
             identity: IdentityConfig::default(),
@@ -3502,6 +3546,7 @@ default_temperature = 0.7
             secrets: SecretsConfig::default(),
             browser: BrowserConfig::default(),
             http_request: HttpRequestConfig::default(),
+            multimodal: MultimodalConfig::default(),
             web_search: WebSearchConfig::default(),
             proxy: ProxyConfig::default(),
             agent: AgentConfig::default(),
@@ -3656,6 +3701,7 @@ tool_dispatcher = "xml"
             secrets: SecretsConfig::default(),
             browser: BrowserConfig::default(),
             http_request: HttpRequestConfig::default(),
+            multimodal: MultimodalConfig::default(),
             web_search: WebSearchConfig::default(),
             proxy: ProxyConfig::default(),
             agent: AgentConfig::default(),