ui: GitHub-Actions-style detail page, sub-steps, mini-tile run-view

Reshapes the detail page into a run-view: hybrid horizontal pipeline
+ expanded active-step pane with sub-steps, a per-step log pane with
line-numbered permalinks and client-side search, and a runs-history
sidebar that navigates via ?run=N. Default step is server-picked
(running → failed → Reporting) so the operator lands on the thing
that's moving.

Adds a sub_steps table + SSE topic (substep-{run}-{stage}-{ordinal})
so per-disk and per-pass work (SMART, CPUStress CPU/RAM, Storage,
GPU) is visible in the UI instead of buried in stage summary JSON.
Agent emits sub-step reports from existing per-iteration loops.

Dashboard tiles become a mini run-view with a 9-dot step strip so
the operator reads run health across the whole grid at a glance.
Register page gets the same card shell + button styling.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

internal/web/templates/registration.templ

@@ -14,53 +14,58 @@ type RegistrationForm struct {
 templ Registration(form RegistrationForm) {
 	@Layout("Register host") {
 		<section class="form-wrap">
-			<h1>Register host</h1>
+			<header class="form-wrap-head">
+				<h1>Register host</h1>
+				<a class="button-secondary" href="/">Back to dashboard</a>
+			</header>
 			if form.Error != "" {
 				<div class="error">{ form.Error }</div>
 			}
 			if form.QuickRegisterURL != "" {
-				<div class="quick-register">
+				<section class="detail-section quick-register">
 					<h2>Quick register <span class="muted">(recommended)</span></h2>
 					<p>Run this on the target host as root before wiping. It auto-detects MAC and hardware, then registers with this orchestrator:</p>
 					<pre class="one-liner"><code>{ "curl -fsSL " + form.QuickRegisterURL + "/register/quick.sh | sudo bash" }</code></pre>
 					<p class="muted">After the script prints <code>OK</code>, refresh the dashboard and click <b>Start vetting</b> on the new host.</p>
-				</div>
+				</section>
 			}
-			<details class="manual-register">
-				<summary>Register manually</summary>
-				<form method="post" action="/hosts" class="host-form">
-					<label>
-						Name
-						<input type="text" name="name" value={ form.Name } required pattern="[A-Za-z0-9_\-\.]+" placeholder="pve-node-03"/>
-					</label>
-					<label>
-						MAC address
-						<input type="text" name="mac" value={ form.MAC } required placeholder="aa:bb:cc:dd:ee:ff"/>
-					</label>
-					<div class="grid-2">
+			<section class="detail-section manual-register-card">
+				<details class="manual-register">
+					<summary><h2>Register manually</h2></summary>
+					<form method="post" action="/hosts" class="host-form">
 						<label>
-							WoL broadcast IP
-							<input type="text" name="wol_broadcast_ip" value={ form.WoLBroadcastIP } required placeholder="10.0.0.255"/>
+							Name
+							<input type="text" name="name" value={ form.Name } required pattern="[A-Za-z0-9_\-\.]+" placeholder="pve-node-03"/>
 						</label>
 						<label>
-							WoL port
-							<input type="number" name="wol_port" value={ defaultPort(form.WoLPort) } min="1" max="65535"/>
+							MAC address
+							<input type="text" name="mac" value={ form.MAC } required placeholder="aa:bb:cc:dd:ee:ff"/>
 						</label>
-					</div>
-					<label>
-						Expected hardware spec (YAML)
-						<textarea name="expected_spec_yaml" rows="12" required placeholder="cpu:&#10;  model_match: ...">{ form.ExpectedSpecYAML }</textarea>
-					</label>
-					<label>
-						Notes
-						<textarea name="notes" rows="3">{ form.Notes }</textarea>
-					</label>
-					<div class="actions">
-						<button type="submit">Register</button>
-						<a class="button-secondary" href="/">Cancel</a>
-					</div>
-				</form>
-			</details>
+						<div class="grid-2">
+							<label>
+								WoL broadcast IP
+								<input type="text" name="wol_broadcast_ip" value={ form.WoLBroadcastIP } required placeholder="10.0.0.255"/>
+							</label>
+							<label>
+								WoL port
+								<input type="number" name="wol_port" value={ defaultPort(form.WoLPort) } min="1" max="65535"/>
+							</label>
+						</div>
+						<label>
+							Expected hardware spec (YAML)
+							<textarea name="expected_spec_yaml" rows="12" required placeholder="cpu:&#10;  model_match: ...">{ form.ExpectedSpecYAML }</textarea>
+						</label>
+						<label>
+							Notes
+							<textarea name="notes" rows="3">{ form.Notes }</textarea>
+						</label>
+						<div class="actions">
+							<button type="submit" class="btn-primary">Register</button>
+							<a class="button-secondary" href="/">Cancel</a>
+						</div>
+					</form>
+				</details>
+			</section>
 		</section>
 	}
 }