feat(mcp): WhatsApp connector, archivable catalog, MCP connector config endpoint

crates/core-api/src/config_property.rs

@@ -1,12 +1,32 @@
 use serde::{Deserialize, Serialize};
 
+/// How a config property is rendered and edited in the Config UI.
+///
+/// Beyond the plain scalars (`String`/`Int`/`Bool`, rendered as text/number/
+/// switch), a variant can stand for a **custom, higher-level control** whose
+/// allowed values are computed by the backend rather than typed by hand —
+/// `SecurityGroup` and `Locale` are both of this kind: they turn into a
+/// dropdown fed by a server-supplied `options` list.
+///
+/// **Adding your own is cheap and encouraged.** If a new config section would
+/// otherwise expose a free-text field where only a fixed/derived set of values
+/// is valid, prefer adding a variant here instead. The wiring is three small,
+/// symmetric edits:
+///   1. add the variant below;
+///   2. in `frontend/api/config.rs`, map it to a type string and (if it's a
+///      dropdown) build its `options: Vec<SelectOption>`;
+///   3. in `web/components/config-page.js`, add a render branch for that type.
+/// Anything carrying `options` renders as a `<select>` — see `_renderInput`.
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
 #[serde(rename_all = "snake_case")]
 pub enum PropertyType {
     String,
     Int,
     Bool,
+    /// Dropdown of the instance's security groups (run-context groups).
     SecurityGroup,
+    /// Dropdown of the interface languages the instance supports.
+    Locale,
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]