Spec #135: owner data-correction actions — Latest Chapter, series_url, Cover, orphan removal (#156)

Implements spec #135 (spec 2 of 4, derived from wayfinder map #114; decisions settled in #120/#121/#125/#131). Blocked-by #134 is merged, so this lands on `main`.

Four owner actions the dashboard can now perform, one ticket each:

- **#149** — Latest Chapter correction: one numeric input, overwritten by the next machine write.
- **#151** — Series URL repair: owner-typed, gated by the poller's own fetch gate.
- **#150 / #153 / #154** — Cover replacement: addresses derived from bytes (`#150`), a Forced Poll replaces the Cover while an ordinary pass still only fills a blank one (`#153`), and byte reclamation is one guarded helper, file first / covers row last (`#154`).
- **#155** — Orphan removal: one Series at a time, with the foreign key as the guard.

Plus **#152** — Latest Chapter provenance: one derived line naming the actor class, so an owner can tell a hand-edited number from a machine read.

- Migration `0015_latest_correction.sql` adds the correction/provenance columns; `0009` now derives cover addresses from bytes.
- ADR `0014-cover-addresses-from-bytes.md` records the address scheme.

Backend tests cover the store, poller, admin handlers, and web routes (`go test ./...`, needs Docker).

Reviewed-on: #156
Co-authored-by: Sulthan Zaki <sultankiki05@gmail.com>
Co-committed-by: Sulthan Zaki <sultankiki05@gmail.com>

backend/internal/web/templates/series-list.html

@@ -4,7 +4,7 @@
      that can be bookmarked: the two selects submit the GET form, and the
      Library segment links and the pager preserve the filter and Site. */}}
 {{define "series-list"}}
-<form class="filterbar" method="get" action="/admin/series">
+<form class="filterbar" id="filterbar" method="get" action="/admin/series">
   <input type="hidden" name="kind" value="{{.Kind}}">
   <label class="fsel"><span>Show</span><select name="filter" onchange="this.form.submit()">
     {{range .Filters}}<option value="{{.Name}}"{{if .Selected}} selected{{end}}>{{.Label}} ({{.Count}})</option>{{end}}
@@ -19,7 +19,7 @@
     <a href="{{.KindNovel}}"{{if eq .Kind "novel"}} class="active"{{end}}>novels</a>
   </span>
 </form>
-<div class="listhead">{{.Total}} series <span class="lbl">· <em>{{.FilterLabel}}</em></span></div>
+{{template "series-list-head" .}}
 {{if .Rows}}
 <div class="tbl series">
   <div class="thead"><span>Site</span><span class="c-ch">Ch</span><span>Checked</span><span class="c-rd">Readers</span><span>Notes</span><span></span></div>
@@ -48,6 +48,16 @@
   <span>{{.Age}}</span>
   <span class="c-rd">{{.Readers}}</span>
   <span class="c-note">{{range .Notes}}<span class="mark">{{.}}</span>{{end}}{{if .More}}<span class="mark mark-faint">+{{.More}}</span>{{end}}</span>
-  <span class="c-act">{{if .CanPoll}}<a class="ghost act" hx-post="/admin/series/{{.Key}}/poll" hx-target="closest .trow" hx-swap="outerHTML" hx-vals='{"band":{{if .Band}}1{{else}}0{{end}}}' href="#">Check now</a>{{end}}</span>
+  <span class="c-act">{{if .CanPoll}}<a class="ghost act" hx-post="/admin/series/{{.Key}}/poll" hx-target="closest .trow" hx-swap="outerHTML" hx-vals='{"band":{{if .Band}}1{{else}}0{{end}}}' href="#">Check now</a>{{end}}{{if .CanRemove}}<button class="ghost danger" hx-post="/admin/series/{{.Key}}/remove" hx-target="closest .trow" hx-swap="outerHTML" hx-include="#filterbar" hx-vals='{"band":{{if .Band}}1{{else}}0{{end}}}' hx-confirm="Removes this series and its stored cover. No Reader has it bookmarked; one re-bookmarking it recreates the row.">Remove</button>{{end}}</span>
+  {{if .RemovalRefused}}<span class="row-msg">a Reader has bookmarked this Series again</span>{{end}}
 </div>
 {{end}}
+
+{{/* series-list-head is the list's heading — the count and the label are one
+     fact. The removal answer renders it out of band (the OOB flag, like the
+     chrome partials) so the heading never lies past the row that made it,
+     and inline here it is the page's own heading. The id is the OOB swap's
+     hook; hx-swap-oob sits on the element the answer carries. */}}
+{{define "series-list-head"}}
+<div class="listhead" id="series-listhead"{{if .OOB}} hx-swap-oob="true"{{end}}>{{.Total}} series <span class="lbl">· <em>{{.FilterLabel}}</em></span></div>
+{{end}}