Add live dashboard with SSE job events

Expose /jobs, /dedup, and /events routes backed by a new EventBus that
broadcasts job lifecycle and per-job progress over SSE. Serve a static
dashboard from front/ that lists pending and in-progress jobs, streams
agent activity, and shows completed reviews.

Also add migrate-apply/migrate-generate scripts that load .env, update
the Containerfile to ship the front assets and use the apply script, and
refresh the roadmap.

front/js/job-list.js

@@ -0,0 +1,58 @@
+// Liste de jobs (une colonne du tableau). Reçoit un tableau de jobs via la
+// propriété `jobs` et l'id sélectionné via `selected`.
+
+import "./job-card.js";
+
+class JobList extends HTMLElement {
+  set jobs(value) {
+    this._jobs = Array.isArray(value) ? value : [];
+    this.render();
+  }
+
+  get jobs() {
+    return this._jobs ?? [];
+  }
+
+  set selected(value) {
+    this._selected = value;
+    this.render();
+  }
+
+  connectedCallback() {
+    if (this._mounted) return;
+    this._mounted = true;
+    this.render();
+  }
+
+  render() {
+    const jobs = this.jobs;
+
+    if (jobs.length === 0) {
+      this.replaceChildren();
+      const empty = document.createElement("p");
+      empty.className = "empty";
+      empty.textContent = this.getAttribute("empty") || "Nothing here.";
+      this.append(empty);
+      return;
+    }
+
+    // Réconciliation par id : on réutilise les cartes existantes pour préserver
+    // l'état replié/déplié de chacune à travers les mises à jour.
+    const known = new Map();
+    for (const card of this.querySelectorAll("steep-job-card")) {
+      if (card.job) known.set(card.job.id, card);
+    }
+
+    for (const job of jobs) {
+      const card = known.get(job.id) ?? document.createElement("steep-job-card");
+      known.delete(job.id);
+      card.job = job;
+      card.selected = job.id === this._selected;
+      this.append(card);
+    }
+
+    for (const card of known.values()) card.remove();
+  }
+}
+
+customElements.define("steep-job-list", JobList);