feat(feedback): in-app user feedback with admin review and account roles

User-facing Feedback screen (Settings -> Info, registered accounts only): a
message (<=1024 runes) plus one optional attachment, an anti-spam gate (one
unreviewed message at a time), and the operator's inline reply with a
Settings/Info badge. Server-rendered admin console section (/_gm/feedback):
unread/read/archived queue with per-user search, detail with read/reply/
archive/delete/delete-all, safe attachment serving (nosniff, images inline via
<img>, others download-only). Introduces account_roles, the first per-account
role table; feedback_banned blocks only feedback submission, granted/revoked
from /users and the delete-with-block action.

- migration 00004_feedback (feedback_messages + account_roles) + jetgen
- backend internal/feedback (store+service), internal/account/roles.go
- wire: FlatBuffers feedback.submit/get/unread; gateway guest gate (Op.NonGuest,
  is_guest via session resolve) -> guest_forbidden before any backend call
- reply push reuses NotificationEvent with a new admin_reply sub-kind
- UI: /feedback route + screen, attachment picker, badge, channel detection, i18n
- tests: feedback unit (Go+UI), gateway guest-gate, inttest lifecycle, e2e
- docs: PLAN stage 19, ARCHITECTURE s15, FUNCTIONAL(+ru), TESTING, READMEs

backend/internal/adminconsole/templates/layout.gohtml

@@ -16,6 +16,7 @@
     <a href="/_gm/users"{{if eq .ActiveNav "users"}} class="active"{{end}}>Users</a>
     <a href="/_gm/games"{{if eq .ActiveNav "games"}} class="active"{{end}}>Games</a>
     <a href="/_gm/complaints"{{if eq .ActiveNav "complaints"}} class="active"{{end}}>Complaints</a>
+    <a href="/_gm/feedback"{{if eq .ActiveNav "feedback"}} class="active"{{end}}>Feedback</a>
     <a href="/_gm/messages"{{if eq .ActiveNav "messages"}} class="active"{{end}}>Messages</a>
     <a href="/_gm/throttled"{{if eq .ActiveNav "throttled"}} class="active"{{end}}>Throttled</a>
     <a href="/_gm/reasons"{{if eq .ActiveNav "reasons"}} class="active"{{end}}>Reasons</a>

backend/internal/adminconsole/templates/pages/dashboard.gohtml

@@ -7,6 +7,7 @@
 <a class="card" href="/_gm/games"><h2>Games</h2><p class="bignum">{{.Games}}</p></a>
 <a class="card" href="/_gm/games?status=active"><h2>Active games</h2><p class="bignum">{{.ActiveGames}}</p></a>
 <a class="card" href="/_gm/complaints?status=open"><h2>Open complaints</h2><p class="bignum">{{.OpenComplaints}}</p></a>
+<a class="card" href="/_gm/feedback?status=unread"><h2>Unread feedback</h2><p class="bignum">{{.OpenFeedback}}</p></a>
 <a class="card" href="/_gm/dictionary"><h2>Pending dict changes</h2><p class="bignum">{{.PendingChanges}}</p></a>
 </div>
 <section class="panel">

backend/internal/adminconsole/templates/pages/feedback.gohtml

@@ -0,0 +1,38 @@
+{{define "content" -}}
+<h1>Feedback</h1>
+{{with .Data}}
+<nav class="subnav">
+<a href="/_gm/feedback?status=unread"{{if eq .Status "unread"}} class="active"{{end}}>unread</a> ·
+<a href="/_gm/feedback?status=read"{{if eq .Status "read"}} class="active"{{end}}>read</a> ·
+<a href="/_gm/feedback?status=archived"{{if eq .Status "archived"}} class="active"{{end}}>archived</a>
+</nav>
+<form class="form" method="get" action="/_gm/feedback">
+<input type="hidden" name="status" value="{{.Status}}">
+{{if .UserID}}<input type="hidden" name="user" value="{{.UserID}}">{{end}}
+<input name="name" value="{{.NameMask}}" placeholder="display name mask (* ?)">
+<input name="ext" value="{{.ExtMask}}" placeholder="external id mask (* ?)">
+<button type="submit">Filter</button>
+</form>
+<table class="list">
+<thead><tr><th>Sender</th><th>Source</th><th>Channel</th><th>Attach</th><th>Reply</th><th>State</th><th>Filed</th></tr></thead>
+<tbody>
+{{range .Items}}
+<tr>
+<td><a href="/_gm/feedback/{{.ID}}">{{.SenderName}}</a></td>
+<td>{{.Source}}</td>
+<td>{{.Channel}}</td>
+<td>{{if .HasAttachment}}yes{{else}}<span class="note">—</span>{{end}}</td>
+<td>{{if .Replied}}<span class="ok">replied</span>{{else}}<span class="note">—</span>{{end}}</td>
+<td>{{if .Archived}}archived{{else if .Read}}read{{else}}<span class="warn">unread</span>{{end}}</td>
+<td>{{.CreatedAt}}</td>
+</tr>
+{{else}}<tr><td colspan="7"><span class="note">no feedback</span></td></tr>{{end}}
+</tbody>
+</table>
+<nav class="pager">
+{{if .Pager.HasPrev}}<a href="/_gm/feedback?{{.FilterQuery}}&amp;page={{.Pager.PrevPage}}">&laquo; prev</a>{{end}}
+<span>page {{.Pager.Page}} · {{.Pager.Total}} total</span>
+{{if .Pager.HasNext}}<a href="/_gm/feedback?{{.FilterQuery}}&amp;page={{.Pager.NextPage}}">next &raquo;</a>{{end}}
+</nav>
+{{end}}
+{{- end}}

backend/internal/adminconsole/templates/pages/feedback_detail.gohtml

@@ -0,0 +1,46 @@
+{{define "content" -}}
+{{with .Data}}
+<h1>Feedback</h1>
+<nav class="subnav"><a href="/_gm/feedback">&laquo; feedback</a> · <a href="/_gm/users/{{.AccountID}}">user</a></nav>
+<section class="panel"><h2>Message</h2>
+<ul class="kv">
+<li><b>From</b> <a href="/_gm/users/{{.AccountID}}">{{.SenderName}}</a> ({{.Source}})</li>
+<li><b>Channel</b> {{.Channel}}</li>
+<li><b>IP</b> {{if .IP}}<code>{{.IP}}</code>{{else}}<span class="note">none</span>{{end}}</li>
+<li><b>Filed</b> {{.CreatedAt}}</li>
+<li><b>State</b> {{if .Archived}}archived{{else if .Read}}read{{else}}<span class="warn">unread</span>{{end}}</li>
+{{if .Banned}}<li><b>Feedback</b> <span class="warn">sender is banned from feedback</span></li>{{end}}
+</ul>
+<div class="msgbody">{{.Body}}</div>
+{{if .HasAttachment}}
+<h3>Attachment</h3>
+{{if .IsImage}}<p><img class="attach" src="/_gm/feedback/{{.ID}}/attachment" alt="attachment"></p>{{end}}
+<p><a href="/_gm/feedback/{{.ID}}/attachment" download>download {{.AttachmentName}}</a></p>
+{{end}}
+</section>
+{{if .Replied}}
+<section class="panel"><h2>Current reply</h2>
+<div class="msgbody">{{.ReplyBody}}</div>
+<p class="note">sent {{.RepliedAt}}</p>
+</section>
+{{end}}
+<section class="panel"><h2>{{if .Replied}}Re-reply{{else}}Reply{{end}}</h2>
+<form class="form col" method="post" action="/_gm/feedback/{{.ID}}/reply">
+<label>Reply <textarea name="reply" required></textarea></label>
+<div><button type="submit">Send reply</button></div>
+</form>
+</section>
+<section class="panel"><h2>Actions</h2>
+<form class="form" method="post" action="/_gm/feedback/{{.ID}}/read"><button type="submit">Mark read</button></form>
+<form class="form" method="post" action="/_gm/feedback/{{.ID}}/archive"><button type="submit">Archive</button></form>
+<form class="form col" method="post" action="/_gm/feedback/{{.ID}}/delete">
+<label><input type="checkbox" name="block" value="1"> ban the player from feedback</label>
+<div><button type="submit">Delete</button></div>
+</form>
+<form class="form col" method="post" action="/_gm/feedback/{{.ID}}/delete-all">
+<label><input type="checkbox" name="block" value="1"> ban the player from feedback</label>
+<div><button type="submit">Delete all from this player</button></div>
+</form>
+</section>
+{{end}}
+{{- end}}

backend/internal/adminconsole/templates/pages/user_detail.gohtml

@@ -1,7 +1,7 @@
 {{define "content" -}}
 {{with .Data}}
 <h1>{{.DisplayName}}</h1>
-<nav class="subnav"><a href="/_gm/users">&laquo; users</a> · <a href="/_gm/messages?user={{.ID}}">messages</a></nav>
+<nav class="subnav"><a href="/_gm/users">&laquo; users</a> · <a href="/_gm/messages?user={{.ID}}">messages</a> · <a href="/_gm/feedback?user={{.ID}}">feedback</a></nav>
 <div class="cards">
 <section class="panel"><h2>Account</h2>
 <ul class="kv">
@@ -67,6 +67,23 @@
 <div><button type="submit">{{if .Suspension.Blocked}}Re-block{{else}}Block{{end}}</button></div>
 </form>
 </section>
+<section class="panel"><h2>Roles</h2>
+{{$id := .ID}}
+{{if .Roles}}
+<table class="list">
+<thead><tr><th>Role</th><th></th></tr></thead>
+<tbody>
+{{range .Roles}}
+<tr><td><code>{{.}}</code></td><td><form class="form" method="post" action="/_gm/users/{{$id}}/revoke-role"><input type="hidden" name="role" value="{{.}}"><button type="submit">Revoke</button></form></td></tr>
+{{end}}
+</tbody>
+</table>
+{{else}}<p class="note">no roles</p>{{end}}
+<form class="form col" method="post" action="/_gm/users/{{$id}}/grant-role">
+<label>Grant role <select name="role">{{range .KnownRoles}}<option value="{{.}}">{{.}}</option>{{end}}</select></label>
+<div><button type="submit">Grant</button></div>
+</form>
+</section>
 {{if .MoveChart}}
 <section class="panel"><h2>Move timing</h2>
 <p class="note">Think time per move number across all games — <span class="lg lg-min">min</span> · <span class="lg lg-avg">mean</span> · <span class="lg lg-max">max</span>.</p>