feat(sender): add manual Webmention resend action

Add an authenticated action to reopen a sent Webmention revision and
queue it for delivery again from the source detail view.

Clear the previous attempt state while preserving historical
successful-send data, and show pending Webmentions explicitly in the UI.

5 files changed, 79 insertions, 14 deletions

diff --git a/webmentions_ssg/templates/includes/confirmation_modal.html b/webmentions_ssg/templates/includes/confirmation_modal.html
index 5c0a5a1..e6a4c10 100644
--- a/webmentions_ssg/templates/includes/confirmation_modal.html
+++ b/webmentions_ssg/templates/includes/confirmation_modal.html
@@ -3,7 +3,7 @@ SPDX-FileCopyrightText: 2026 Dennis Fink <me+coding@dennisfink.me>
 
 SPDX-License-Identifier: BSD-3-Clause
 -->
-
+{% from "bootstrap5/form.html" import render_form %}
 <div class="modal fade"
      id="confirmation-modal"
      tabindex="-1"
diff --git a/webmentions_ssg/templates/received.html b/webmentions_ssg/templates/received.html
index 1c5a216..7cfdce8 100644
--- a/webmentions_ssg/templates/received.html
+++ b/webmentions_ssg/templates/received.html
@@ -3,9 +3,7 @@ SPDX-FileCopyrightText: 2026 Dennis Fink <me+coding@dennisfink.me>
 
 SPDX-License-Identifier: BSD-3-Clause
 -->
-
 {% extends "base.html" %}
-{% from "bootstrap5/form.html" import render_form %}
 {% from "bootstrap5/pagination.html" import render_pagination %}
 {% block content %}
   <div class="d-flex justify-content-between align-items-center mb-3">
diff --git a/webmentions_ssg/templates/sent.html b/webmentions_ssg/templates/sent.html
index 1d311a0..4ca75ce 100644
--- a/webmentions_ssg/templates/sent.html
+++ b/webmentions_ssg/templates/sent.html
@@ -3,9 +3,7 @@ SPDX-FileCopyrightText: 2026 Dennis Fink <me+coding@dennisfink.me>
 
 SPDX-License-Identifier: BSD-3-Clause
 -->
-
 {% extends "base.html" %}
-{% from "bootstrap5/form.html" import render_form %}
 {% from "bootstrap5/pagination.html" import render_pagination %}
 {% block content %}
   <div class="d-flex justify-content-between align-items-center mb-3">
@@ -50,7 +48,7 @@ SPDX-License-Identifier: BSD-3-Clause
             {% endif %}
             <tr class="{{ row_class }}">
               <td class="text-nowrap">
-                <a href="{{ url_for('root.sent_source', identifier=source.uuid) }}">{{ source.path }}</a>
+                <a href="{{ url_for('root.sent_source', source_identifier=source.uuid) }}">{{ source.path }}</a>
               </td>
               <td class="text-break">
                 <a href="{{ source.url }}">{{ source.url }}</a>
diff --git a/webmentions_ssg/templates/sent_source.html b/webmentions_ssg/templates/sent_source.html
index 6bb2ac5..77376b5 100644
--- a/webmentions_ssg/templates/sent_source.html
+++ b/webmentions_ssg/templates/sent_source.html
@@ -3,7 +3,6 @@ SPDX-FileCopyrightText: 2026 Dennis Fink <me+coding@dennisfink.me>
 
 SPDX-License-Identifier: BSD-3-Clause
 -->
-
 {% extends "base.html" %}
 {% block content %}
   <div class="mb-3">
@@ -85,11 +84,15 @@ SPDX-License-Identifier: BSD-3-Clause
             <th scope="col">Status URL</th>
             <th scope="col">Last attempted at</th>
             <th scope="col">Last sent at</th>
+            <th scope="col">Actions</th>
           </tr>
         </thead>
         <tbody>
           {% for webmention in webmentions %}
-            {% if webmention.status.value == "sent" %}
+            {% if webmention.status is none %}
+              {% set row_class = "table-info" %}
+              {% set badge_class = "text-bg-info" %}
+            {% elif webmention.status.value == "sent" %}
               {% set row_class = "table-success" %}
               {% set badge_class = "text-bg-success" %}
             {% elif webmention.status.value == "unsupported" %}
@@ -107,7 +110,9 @@ SPDX-License-Identifier: BSD-3-Clause
                 <a href="{{ webmention.target }}">{{ webmention.target }}</a>
               </td>
               <td>
-                {% if webmention.status is not none %}
+                {% if webmention.status is none %}
+                  <span class="badge {{ badge_class }}">Pending</span>
+                {% else %}
                   <span class="badge {{ badge_class }}">{{ webmention.status.value.title() }}</span>
                 {% endif %}
               </td>
@@ -171,12 +176,28 @@ SPDX-License-Identifier: BSD-3-Clause
                   —
                 {% endif %}
               </td>
+              <td>
+                <button type="button"
+                        class="btn btn-sm btn-primary"
+                        data-bs-toggle="modal"
+                        data-bs-target="#confirmation-modal"
+                        data-action="{{ url_for("root.resend_sent_webmention", source_identifier=source.uuid, webmention_identifier=webmention.uuid) }}"
+                        data-title="Resend Webmention?"
+                        data-message="This Webmention will be queued again for delivery to {{ webmention.target }}."
+                        data-confirm-label="Resend"
+                        data-confirm-class="btn-primary">Resend</button>
+              </td>
             </tr>
           {% endfor %}
         </tbody>
       </table>
     </div>
+    {% include "includes/confirmation_modal.html" %}
   {% else %}
     <p class="text-body-secondary">No Webmentions have been discovered for this source.</p>
   {% endif %}
 {% endblock %}
+{% block scripts %}
+  {{ super() }}
+  <script src="{{ url_for('static', filename='js/confirmation-modal.js') }}"></script>
+{% endblock %}
diff --git a/webmentions_ssg/views.py b/webmentions_ssg/views.py
index 3430cea..2235735 100644
--- a/webmentions_ssg/views.py
+++ b/webmentions_ssg/views.py
@@ -24,9 +24,10 @@ from sqlalchemy.orm import selectinload
 
 from . import CSRF, forms
 from . import DATABASE as db
-from .models import ReceivedWebmention, Source, User
+from .models import ReceivedWebmention, SentWebmention, Source, User
 from .tasks.receiver import verify_webmention
 from .tasks.scanner import manual_scan_sources
+from .tasks.sender import send_webmention
 
 root_page = Blueprint("root", __name__)
 
@@ -209,19 +210,19 @@ def rescan_sent_sources() -> ResponseReturnValue:
     return redirect(url_for("root.sent"))
 
 
-@root_page.route("/sent/<uuid:identifier>")
+@root_page.route("/sent/<uuid:source_identifier>")
 @login_required
-def sent_source(identifier: uuid.UUID) -> ResponseReturnValue:
+def sent_source(source_identifier: uuid.UUID) -> ResponseReturnValue:
     """
     Display the sent Webmentions associated with a source.
 
-    :param identifier: Identifier of the source to display.
+    :param source_identifier: Identifier of the source to display.
     :return: Rendered source details page.
     """
     source = db.session.scalar(
         sa.select(Source)
         .options(selectinload(Source.sent_webmentions))
-        .where(Source.uuid == identifier)
+        .where(Source.uuid == source_identifier)
     )
     if source is None:
         return abort(404)
@@ -234,9 +235,56 @@ def sent_source(identifier: uuid.UUID) -> ResponseReturnValue:
         title="Sent Webmentions",
         source=source,
         webmentions=webmentions,
+        action_form=forms.AdminActionForm(),
     )
 
 
+@root_page.post("/sent/<uuid:source_identifier>/<uuid:webmention_identifier>/resend")
+@login_required
+def resend_sent_webmention(
+    source_identifier: uuid.UUID, webmention_identifier: uuid.UUID
+) -> ResponseReturnValue:
+    """
+    Queue an outgoing Webmention to be sent again.
+
+    The current desired source revision is reopened for processing so the
+    sender task does not treat the Webmention as already completed. Historical
+    successful-send fields are preserved, while result fields from the previous
+    attempt are cleared.
+
+    :param source_identifier: Identifier of the source owning the Webmention.
+    :param webmention_identifier: Identifier of the sent Webmention to resend.
+    :return: Redirect response to the source details view.
+    """
+    form = forms.AdminActionForm()
+
+    if not form.validate_on_submit():
+        return abort(400)
+
+    webmention = db.session.get(SentWebmention, webmention_identifier)
+
+    if webmention is None or webmention.source_id != source_identifier:
+        return abort(404)
+
+    # Reopen the existing desired revision instead of inventing a new source
+    # revision. send_webmention() otherwise exits when this revision has already
+    # been processed.
+    webmention.processed_revision = None
+    webmention.status = None
+    webmention.failure_reason = None
+    webmention.endpoint = None
+    webmention.response_status = None
+    webmention.status_url = None
+
+    db.session.commit()
+
+    send_webmention(webmention_identifier)
+
+    flash(f"Webmention {webmention.uuid} queued for resend.", "success")
+
+    return redirect(url_for("root.sent_source", identifier=source_identifier))
+
+
 @root_page.post("/endpoint")
 @CSRF.exempt
 def endpoint() -> ResponseReturnValue: