feat(watcher): Ajout watcher de fichiers temps réel

- Migration 0006: colonne watcher_enabled
- Crate notify pour surveillance FS temps réel (FSEvents/inotify)
- Watcher redémarré toutes les 30s si config change
- Détection instantanée création/modification/suppression
- Création job immédiate quand fichier détecté
- API: support watcher_enabled dans UpdateMonitoringRequest
- Backoffice: toggle Watcher avec indicateur ⚡
- Fonctionne en parallèle du scheduler auto-scan

Usage: Activer Watcher + Auto-scan pour réactivité max

apps/indexer/src/main.rs

@@ -2,12 +2,14 @@ use anyhow::Context;
 use axum::{extract::State, routing::get, Json, Router};
 use chrono::{DateTime, Utc};
 use axum::http::StatusCode;
+use notify::{Config, Event, RecommendedWatcher, RecursiveMode, Watcher};
 use parsers::{detect_format, parse_metadata, BookFormat};
 use serde::Serialize;
 use sha2::{Digest, Sha256};
 use sqlx::{postgres::PgPoolOptions, Row};
 use std::{collections::HashMap, path::Path, time::Duration};
 use stripstream_core::config::IndexerConfig;
+use tokio::sync::mpsc;
 use tracing::{error, info, trace, warn};
 use uuid::Uuid;
 use walkdir::WalkDir;
@@ -92,6 +94,16 @@ async fn ready(State(state): State<AppState>) -> Result<Json<serde_json::Value>,
 
 async fn run_worker(state: AppState, interval_seconds: u64) {
     let wait = Duration::from_secs(interval_seconds.max(1));
+
+    // Start file watcher task
+    let watcher_state = state.clone();
+    let _watcher_handle = tokio::spawn(async move {
+        info!("[WATCHER] Starting file watcher service");
+        if let Err(err) = run_file_watcher(watcher_state).await {
+            error!("[WATCHER] Error: {}", err);
+        }
+    });
+
     // Start scheduler task for auto-monitoring
     let scheduler_state = state.clone();
     let _scheduler_handle = tokio::spawn(async move {
@@ -127,6 +139,140 @@ async fn run_worker(state: AppState, interval_seconds: u64) {
     }
 }
 
+async fn run_file_watcher(state: AppState) -> anyhow::Result<()> {
+    let (tx, mut rx) = mpsc::channel::<(Uuid, String)>(100);
+
+    // Start watcher refresh loop
+    let refresh_interval = Duration::from_secs(30);
+    let pool = state.pool.clone();
+
+    tokio::spawn(async move {
+        let mut watcher: Option<RecommendedWatcher> = None;
+        let mut watched_libraries: HashMap<Uuid, String> = HashMap::new();
+
+        loop {
+            // Get libraries with watcher enabled
+            match sqlx::query(
+                "SELECT id, root_path FROM libraries WHERE watcher_enabled = TRUE AND enabled = TRUE"
+            )
+            .fetch_all(&pool)
+            .await
+            {
+                Ok(rows) => {
+                    let current_libraries: HashMap<Uuid, String> = rows
+                        .into_iter()
+                        .map(|row| {
+                            let id: Uuid = row.get("id");
+                            let root_path: String = row.get("root_path");
+                            let local_path = remap_libraries_path(&root_path);
+                            (id, local_path)
+                        })
+                        .collect();
+
+                    // Check if we need to recreate watcher
+                    let needs_restart = watched_libraries.len() != current_libraries.len()
+                        || watched_libraries.iter().any(|(id, path)| {
+                            current_libraries.get(id) != Some(path)
+                        });
+
+                    if needs_restart {
+                        info!("[WATCHER] Restarting watcher for {} libraries", current_libraries.len());
+
+                        // Drop old watcher
+                        watcher = None;
+                        watched_libraries.clear();
+
+                        if !current_libraries.is_empty() {
+                            let tx_clone = tx.clone();
+                            let libraries_clone = current_libraries.clone();
+
+                            match setup_watcher(libraries_clone, tx_clone) {
+                                Ok(new_watcher) => {
+                                    watcher = Some(new_watcher);
+                                    watched_libraries = current_libraries;
+                                    info!("[WATCHER] Watching {} libraries", watched_libraries.len());
+                                }
+                                Err(err) => {
+                                    error!("[WATCHER] Failed to setup watcher: {}", err);
+                                }
+                            }
+                        }
+                    }
+                }
+                Err(err) => {
+                    error!("[WATCHER] Failed to fetch libraries: {}", err);
+                }
+            }
+
+            tokio::time::sleep(refresh_interval).await;
+        }
+    });
+
+    // Process watcher events
+    while let Some((library_id, file_path)) = rx.recv().await {
+        info!("[WATCHER] File changed in library {}: {}", library_id, file_path);
+
+        // Check if there's already a pending job for this library
+        match sqlx::query_scalar::<_, bool>(
+            "SELECT EXISTS(SELECT 1 FROM index_jobs WHERE library_id = $1 AND status IN ('pending', 'running'))"
+        )
+        .bind(library_id)
+        .fetch_one(&state.pool)
+        .await
+        {
+            Ok(exists) => {
+                if !exists {
+                    // Create a quick scan job
+                    let job_id = Uuid::new_v4();
+                    match sqlx::query(
+                        "INSERT INTO index_jobs (id, library_id, type, status) VALUES ($1, $2, 'rebuild', 'pending')"
+                    )
+                    .bind(job_id)
+                    .bind(library_id)
+                    .execute(&state.pool)
+                    .await
+                    {
+                        Ok(_) => info!("[WATCHER] Created job {} for library {}", job_id, library_id),
+                        Err(err) => error!("[WATCHER] Failed to create job: {}", err),
+                    }
+                } else {
+                    trace!("[WATCHER] Job already pending for library {}, skipping", library_id);
+                }
+            }
+            Err(err) => error!("[WATCHER] Failed to check existing jobs: {}", err),
+        }
+    }
+
+    Ok(())
+}
+
+fn setup_watcher(
+    libraries: HashMap<Uuid, String>,
+    tx: mpsc::Sender<(Uuid, String)>,
+) -> anyhow::Result<RecommendedWatcher> {
+    let watcher = notify::recommended_watcher(move |res: Result<Event, notify::Error>| {
+        match res {
+            Ok(event) => {
+                if event.kind.is_modify() || event.kind.is_create() || event.kind.is_remove() {
+                    for path in event.paths {
+                        if let Some((library_id, _)) = libraries.iter().find(|(_, root)| {
+                            path.starts_with(root)
+                        }) {
+                            let path_str = path.to_string_lossy().to_string();
+                            if detect_format(&path).is_some() {
+                                let _ = tx.try_send((*library_id, path_str));
+                            }
+                        }
+                    }
+                }
+            }
+            Err(err) => error!("[WATCHER] Event error: {}", err),
+        }
+    })?;
+
+    Ok(watcher)
+}
+
 async fn check_and_schedule_auto_scans(pool: &sqlx::PgPool) -> anyhow::Result<()> {
     let libraries = sqlx::query(
         r#"