Add GET /enhance/prompts: recent distinct Enhance prompts

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

src/enhance/handlers.rs

@@ -3,6 +3,7 @@
 //!
 //! - `GET  /enhance/templates`
 //! - `POST /enhance`
+//! - `GET  /enhance/prompts?templates=&limit=`
 //! - `GET  /enhance/jobs?path=`
 //! - `GET  /enhance/jobs/{id}`
 //! - `GET  /enhance/jobs/{id}/preview/{n}`
@@ -363,6 +364,57 @@ pub async fn list_jobs(
     }
 }
 
+#[derive(Debug, Deserialize)]
+pub struct PromptsQuery {
+    /// Comma-separated template names; omitted = all templates.
+    pub templates: Option<String>,
+    pub limit: Option<i64>,
+}
+
+#[derive(Debug, Serialize)]
+struct PromptView {
+    prompt: String,
+    template: String,
+    last_used: i64,
+    uses: i64,
+}
+
+/// Prompts used before, newest first, so the app can offer them again for a
+/// series of similar photos. DB only: not library-scoped, and answered even
+/// when ComfyUI is down or Enhance is off (then simply from old rows).
+#[get("/enhance/prompts")]
+pub async fn recent_prompts(
+    _: Claims,
+    q: web::Query<PromptsQuery>,
+    svc: web::Data<EnhanceService>,
+) -> impl Responder {
+    let names: Option<Vec<String>> = q.templates.as_deref().map(|t| {
+        t.split(',')
+            .map(str::trim)
+            .filter(|n| !n.is_empty())
+            .map(str::to_string)
+            .collect()
+    });
+    // `templates=` with nothing in it means "no filter", like omitting it.
+    let names = names.filter(|n| !n.is_empty());
+    let limit = q.limit.unwrap_or(10).clamp(1, 50);
+    match svc.recent_prompts(names.as_deref(), limit) {
+        Ok(rows) => {
+            let prompts: Vec<PromptView> = rows
+                .into_iter()
+                .map(|r| PromptView {
+                    prompt: r.prompt,
+                    template: r.template,
+                    last_used: r.last_used,
+                    uses: r.uses,
+                })
+                .collect();
+            HttpResponse::Ok().json(json!({ "prompts": prompts }))
+        }
+        Err(e) => error_response(&e),
+    }
+}
+
 #[get("/enhance/jobs/{id}/preview/{n}")]
 pub async fn preview(
     _: Claims,