Web dashboard step 1: migration, sessions, users CLI, public site

Migration 0004 (users, sessions, config_changes, profile_versions, jobs,
rating_events.user_id, runs.report_json, issues.issue_json), the issue
snapshot writer and loader, the web module skeleton with layout and static
assets, axum-login/tower-sessions over a sqlx session store, password-auth
users with a CLI, the login throttle, the origin check, security headers,
and the public issue pages, archive, Atom feed and robots.txt.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NHyYupFdBiR4VfoUM7NjSM

src/curate/profile/mod.rs

@@ -509,6 +509,7 @@ mod tests {
     fn prompt_sections_are_ordered_and_verdicts_have_required_labels() {
         let rating = RatedArticle {
             article_id: 1,
+            user_id: None,
             issue_date: None,
             title: "A title".into(),
             feed_title: "A feed".into(),
@@ -551,6 +552,7 @@ mod tests {
     fn rebuild_prompt_carries_summary_facets_note_and_diversity_instruction() {
         let rating = RatedArticle {
             article_id: 1,
+            user_id: None,
             issue_date: Some("2026-08-15".parse().unwrap()),
             title: "Postgres failover".into(),
             feed_title: "Engineering Notes".into(),
@@ -647,6 +649,7 @@ mod tests {
         .unwrap();
         db.append_rating_event(&RatingEvent {
             id: 0,
+            user_id: None,
             article_id: 1,
             issue_date: None,
             kind: "explicit".into(),