feat(audio-player): Resume Rewind select in the settings popover

The player window could only change Skip and Speed; resume rewind
lived exclusively on the profile page. The user-facing settings now
match Speed's precedent — changeable from the player, saved to the
account, applied immediately.

The select mirrors the default-speed row (CSP-safe @change bound to
one Alpine method; templ emits the option list from the shared
ResumeRewindOptions allow-list and the :selected expression against
the live resumeRewind field). Applying updates the running player's
value first — the next open/unpause uses it with no reload — then
PUTs audio_resume_rewind_seconds to the profile endpoint as the
string wire shape the server binds. normalizeResumeRewind gates the
select's value through 0/5/10 before both steps.

templates/audio_reader.templ

@@ -255,6 +255,25 @@ templ AudioReader(user User, metadata ReaderMetadata) {
 								}
 								</select>
 							</div>
+							<!-- Resume rewind — player-side control of the
+							     account setting (the profile page keeps
+							     its select; same PUT, applied live). -->
+							<div class="flex items-center justify-between gap-3 px-1 py-2 rounded-lg">
+								<span class="text-sm" style="color: var(--text-secondary);">Resume rewind</span>
+								<select
+									class="text-xs rounded-md px-1.5 py-1"
+									style="background-color: var(--surface-hover); color: var(--text-primary); border: 1px solid var(--border);"
+									aria-label="Resume rewind"
+									@change="applyResumeRewindFromSelect($event)"
+								>
+								for _, secs := range ResumeRewindOptions {
+									<option
+										value={ fmt.Sprintf("%d", secs) }
+										:selected={ fmt.Sprintf("resumeRewind === %d", secs) }
+									>{ ResumeRewindLabel(secs) }</option>
+								}
+								</select>
+							</div>
 						</div>
 					</div>
 				</span>