refactor(hosts): remove legacy host_agent redirects/paths (no back-compat)

Dev-only instance, no bookmarks — per family rule 22, fully remove old paths
instead of shimming them.

- Delete the /plugins/host_agent/ (index) and /plugins/host_agent/settings/
  redirect routes; delete the now-dead host_list.html fleet template.
- Move the remaining management POST routes off /settings/ to /fleet/
  (add-host, rotate-token, delete) — single canonical prefix.
- Repoint real callers to canonical URLs: dashboard widgets (host resources →
  /hosts/, history → /plugins/host_agent/fleet/), the full-metrics page
  breadcrumb + back link (→ the host hub), Settings→Ansible link, and the
  agent panel's curl-install link.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

plugins/host_agent/routes.py

@@ -372,14 +372,6 @@ async def _fleet_rows(session) -> list[dict]:
     return rows
 
 
-@host_agent_bp.get("/")
-@require_role(UserRole.viewer)
-async def index():
-    """The fleet view folded into the Hosts hub — kept as a redirect so old
-    links/widgets don't 404."""
-    return redirect("/hosts/")
-
-
 @host_agent_bp.get("/widget")
 async def widget_table():
     """Fleet-glance dashboard widget: one row per monitored host, latest metrics."""
@@ -568,13 +560,6 @@ async def host_panel(host_id: str):
     )
 
 
-@host_agent_bp.get("/settings/")
-@require_role(UserRole.admin)
-async def settings_redirect():
-    """Old management URL — agent management moved into the Hosts section."""
-    return redirect(url_for("host_agent.fleet"))
-
-
 @host_agent_bp.get("/fleet/")
 @require_role(UserRole.admin)
 async def fleet():
@@ -618,7 +603,7 @@ async def fleet():
     )
 
 
-@host_agent_bp.post("/settings/add-host")
+@host_agent_bp.post("/fleet/add-host")
 @require_role(UserRole.admin)
 async def add_host():
     form = await request.form
@@ -650,7 +635,7 @@ async def add_host():
     return redirect(url_for("host_agent.fleet") + f"?new_token={raw}&host_id={host_id}")
 
 
-@host_agent_bp.post("/settings/<host_id>/rotate-token")
+@host_agent_bp.post("/fleet/<host_id>/rotate-token")
 @require_role(UserRole.admin)
 async def rotate_token(host_id: str):
     async with current_app.db_sessionmaker() as session:
@@ -666,7 +651,7 @@ async def rotate_token(host_id: str):
     return redirect(url_for("host_agent.fleet") + f"?new_token={raw}&host_id={host_id}")
 
 
-@host_agent_bp.post("/settings/<host_id>/delete")
+@host_agent_bp.post("/fleet/<host_id>/delete")
 @require_role(UserRole.admin)
 async def delete_registration(host_id: str):
     async with current_app.db_sessionmaker() as session:

plugins/host_agent/templates/host_detail.html

@@ -1,7 +1,7 @@
 {% extends "base.html" %}
 {% from "_macros.html" import crumbs %}
 {% block title %}{{ host.name }} — Host Agent — Steward{% endblock %}
-{% block breadcrumb %}{{ crumbs([("Host Agents", "/plugins/host_agent/"), (host.name, "")]) }}{% endblock %}
+{% block breadcrumb %}{{ crumbs([("Hosts", "/hosts/"), (host.name, "/hosts/" ~ host.id), ("Metrics", "")]) }}{% endblock %}
 
 {% macro fmt_bps(v) %}
 {%- if v is none -%}—
@@ -27,7 +27,7 @@
 {% block content %}
 <div style="display:flex;align-items:center;justify-content:space-between;gap:1rem;flex-wrap:wrap;margin-bottom:0.75rem;">
   <div style="display:flex;align-items:center;gap:0.6rem;">
-    <a href="/plugins/host_agent/" class="btn btn-ghost btn-sm">← Fleet</a>
+    <a href="/hosts/{{ host.id }}" class="btn btn-ghost btn-sm">← Host</a>
     <h1 class="page-title" style="margin-bottom:0;">{{ host.name }}</h1>
     {% if stale %}<span class="badge badge-red">stale</span>{% else %}<span class="badge badge-green">live</span>{% endif %}
   </div>

plugins/host_agent/templates/host_list.html

@@ -1,45 +0,0 @@
-{% extends "base.html" %}
-{% from "_macros.html" import crumbs %}
-{% block title %}Host Agents — Steward{% endblock %}
-{% block breadcrumb %}{{ crumbs([("Dashboard", "/"), ("Host Agents", "")]) }}{% endblock %}
-{% block content %}
-<div style="display:flex;align-items:center;justify-content:space-between;margin-bottom:1.25rem;gap:1rem;flex-wrap:wrap;">
-  <h1 class="page-title" style="margin-bottom:0;">Host Agents</h1>
-  {% if session.user_role == 'admin' %}
-  <a class="btn btn-ghost" href="/plugins/host_agent/settings/">Manage agents →</a>
-  {% endif %}
-</div>
-
-{% if not rows %}
-<div class="card empty">
-  No hosts are reporting agent metrics yet.
-  {% if session.user_role == 'admin' %}
-  Add one from <a href="/plugins/host_agent/settings/">Host Agent settings</a> and run the install command on the target.
-  {% else %}
-  Ask an admin to install the agent on a host.
-  {% endif %}
-</div>
-{% else %}
-<div style="display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:1rem;">
-{% for r in rows %}
-  <a href="/plugins/host_agent/{{ r.host.id }}/" class="card" style="display:block;margin-bottom:0;color:inherit;">
-    <div style="display:flex;align-items:center;gap:0.5rem;margin-bottom:0.7rem;">
-      <span class="dot {% if r.stale %}dot-dim{% elif (r.cpu_pct or 0) >= 90 or (r.mem_used_pct or 0) >= 90 or (r.disk_worst or 0) >= 90 %}dot-warn{% else %}dot-up{% endif %}"></span>
-      <span style="font-weight:600;flex:1;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;">{{ r.host.name }}</span>
-      {% if r.stale %}<span class="badge badge-dim">stale</span>{% endif %}
-    </div>
-    <div style="display:grid;grid-template-columns:1fr 1fr;gap:0.45rem 0.9rem;font-size:0.84rem;font-variant-numeric:tabular-nums;">
-      <span><span style="color:var(--text-dim);">CPU</span> {% if r.cpu_pct is not none %}{{ "%.0f"|format(r.cpu_pct) }}%{% else %}—{% endif %}</span>
-      <span><span style="color:var(--text-dim);">Mem</span> {% if r.mem_used_pct is not none %}{{ "%.0f"|format(r.mem_used_pct) }}%{% else %}—{% endif %}</span>
-      <span><span style="color:var(--text-dim);">Disk</span> {% if r.disk_worst is not none %}{{ "%.0f"|format(r.disk_worst) }}%{% else %}—{% endif %}</span>
-      <span><span style="color:var(--text-dim);">Load</span> {% if r.load_1m is not none %}{{ "%.2f"|format(r.load_1m) }}{% else %}—{% endif %}</span>
-      {% if r.temp_max is not none %}<span><span style="color:var(--text-dim);">Temp</span> {{ "%.0f"|format(r.temp_max) }}°C</span>{% endif %}
-    </div>
-    <div style="margin-top:0.6rem;font-size:0.72rem;color:var(--text-dim);">
-      last seen {{ r.reg.last_seen_at.strftime("%Y-%m-%d %H:%M:%S") ~ " UTC" if r.reg.last_seen_at else "never" }}
-    </div>
-  </a>
-{% endfor %}
-</div>
-{% endif %}
-{% endblock %}

plugins/host_agent/templates/panel.html

@@ -37,11 +37,11 @@
       <button type="submit" class="btn btn-sm" title="Refresh agent.py + restart (token preserved)">Update agent</button>
     </form>
     {% endif %}
-    <form method="post" action="/plugins/host_agent/settings/{{ host.id }}/rotate-token" style="margin:0;"
+    <form method="post" action="/plugins/host_agent/fleet/{{ host.id }}/rotate-token" style="margin:0;"
           onsubmit="return confirm('Rotate token? The agent stops reporting until reinstalled/updated with the new token.');">
       <button type="submit" class="btn btn-sm btn-ghost">Rotate token</button>
     </form>
-    <form method="post" action="/plugins/host_agent/settings/{{ host.id }}/delete" style="margin:0;"
+    <form method="post" action="/plugins/host_agent/fleet/{{ host.id }}/delete" style="margin:0;"
           onsubmit="return confirm('Remove this agent registration? Metrics stop until re-registered.');">
       <button type="submit" class="btn btn-sm btn-danger">Remove</button>
     </form>
@@ -65,7 +65,7 @@
   {% elif not ansible_available %}
   <p style="color:var(--text-dim);font-size:0.85rem;">
     Ansible isn't available, so the agent can't be deployed from here. Install it manually with the
-    <a href="/plugins/host_agent/settings/">curl install command</a>.
+    <a href="/plugins/host_agent/fleet/">curl install command</a>.
   </p>
 
   {% elif not managed_key_set %}

plugins/host_agent/templates/settings_list.html

@@ -23,7 +23,7 @@
 {% endif %}
 
 <div class="card">
-  <form method="post" action="/plugins/host_agent/settings/add-host"
+  <form method="post" action="/plugins/host_agent/fleet/add-host"
         style="display:flex;gap:0.75rem;align-items:flex-end;flex-wrap:wrap;">
     <div class="form-group" style="margin-bottom:0;">
       <label>Host name</label>
@@ -155,12 +155,12 @@
         <td>{{ item.reg.distro or "—" }}</td>
         <td>{{ item.reg.last_seen_at.strftime("%Y-%m-%d %H:%M:%S") if item.reg.last_seen_at else "never" }}</td>
         <td class="td-actions">
-          <form method="post" action="/plugins/host_agent/settings/{{ item.reg.host_id }}/rotate-token"
+          <form method="post" action="/plugins/host_agent/fleet/{{ item.reg.host_id }}/rotate-token"
                 style="display:inline;"
                 onsubmit="return confirm('Rotate the token for this host? The existing agent will stop working until reinstalled with the new token.');">
             <button type="submit" class="btn btn-ghost btn-sm">Rotate token</button>
           </form>
-          <form method="post" action="/plugins/host_agent/settings/{{ item.reg.host_id }}/delete"
+          <form method="post" action="/plugins/host_agent/fleet/{{ item.reg.host_id }}/delete"
                 style="display:inline;"
                 onsubmit="return confirm('Delete this host registration? The agent will be unable to report metrics until re-registered.');">
             <button type="submit" class="btn btn-danger btn-sm">Delete</button>

steward/core/widgets.py

@@ -262,7 +262,7 @@ WIDGET_REGISTRY: dict[str, dict] = {
         "label": "Host Agent — Resources",
         "description": "Fleet view: CPU, memory, disk, and load per monitored host",
         "hx_url": "/plugins/host_agent/widget",
-        "detail_url": "/plugins/host_agent/",
+        "detail_url": "/hosts/",
         "plugin": "host_agent",
         "poll": True,
         "params": [],
@@ -272,7 +272,7 @@ WIDGET_REGISTRY: dict[str, dict] = {
         "label": "Host Agent — History",
         "description": "CPU/memory/disk history for one host",
         "hx_url": "/plugins/host_agent/widget/history",
-        "detail_url": "/plugins/host_agent/settings/",
+        "detail_url": "/plugins/host_agent/fleet/",
         "plugin": "host_agent",
         "poll": True,
         "params": [

steward/templates/settings/ansible.html

@@ -29,7 +29,7 @@
       Steward's reusable Ansible identity. Provisioning installs the <strong>public</strong>
       key into each host's <code>{{ ssh_user }}</code> account; steady-state runs authenticate
       with the private half (stored encrypted). Generate it once, then provision hosts from
-      <a href="/plugins/host_agent/settings/">Host Agents</a>.
+      <a href="/plugins/host_agent/fleet/">Host Agents</a>.
     </p>
     {% if ssh_public_key %}
     <div class="form-group">