v0.4.0: upload telemetry, host log, jet-black UI

- Upload reliability + diagnostics:
  - api_upload_iso now distinguishes clean EOF from mid-stream errors;
    a truncated multipart body (proxy buffer cap, network drop) returns
    400 with the cause and a "try the LAN IP" hint instead of silently
    finalising a partial file.
  - Per-stage tracing (begin/MB-watermark/finish/abort) so a stuck
    upload is debuggable from the Terminal tab.
  - Web upload UI surfaces bytes/total, percent, throughput, ETA, and
    maps 413/502/504/network-drop to actionable hints.
- New BootLog feature under Hosts:
  - openpxe-core::BootLog — bounded in-memory ring (500) + append-only
    JSONL on disk, recording (timestamp, mac, ip, target_id,
    target_title) every time a boot entry script is served.
  - iPXE per-entry chain URLs grow ?mac=${mac}; password prompt
    submission carries it through; host-binding short-circuit uses the
    bound MAC. ConnectInfo<SocketAddr> wired for peer IP capture (with
    optional fallback so tower::oneshot in tests still works).
  - GET /api/boot-log endpoint + Host log table under the Hosts tab.
- UI changes:
  - Queue card header "Forge" → "Status".
  - Removed Tinkerbell attribution sentence from Hosts tab.
  - Topbar readiness chip moved into the sidebar footer as
    "Service status: Ready / Advertised to clients / <url>", grouping
    advertised PXE URL with operator-relevant status.
  - Jet-black dark palette (#000 / #0a0a0a / #141414 / #1c1c1c)
    replacing the blue-tinted ramp; terminal toolbar/input recoloured
    to match.
- 89 tests passing (was 85 in v0.3.2); cargo clippy --workspace
  --all-targets clean.

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

crates/webui/src/index.html

@@ -29,7 +29,7 @@
       <img src="/assets/logo.svg" alt="" />
       <div>
         <strong>OpenPXE</strong>
-        <div class="sub">v<span data-bind="version">0.3.2</span></div>
+        <div class="sub">v<span data-bind="version">0.4.0</span></div>
       </div>
     </div>
     <nav>
@@ -51,7 +51,12 @@
       <a data-view="about">About</a>
     </nav>
     <div class="footer">
-      Advertised to clients<br/>
+      <div class="status-row">
+        <span class="dot" data-bind="ready_dot" title="Server readiness"></span>
+        <span class="status-label">Service status:</span>
+        <span class="status-value" data-bind="ready_label">checking…</span>
+      </div>
+      <div class="footer-sub">Advertised to clients</div>
       <code>{{BASE_URL}}</code>
     </div>
   </aside>
@@ -59,7 +64,6 @@
   <header class="topbar">
     <h1 data-bind="view_title">Dashboard</h1>
     <div class="spacer"></div>
-    <span class="chip" data-bind="ready_chip" title="Server readiness">checking…</span>
     <span class="chip"><strong data-bind="iso_count2">0</strong>&nbsp;images</span>
     <span class="chip"><strong data-bind="client_count2">0</strong>&nbsp;clients</span>
     <span class="chip"><strong data-bind="queue_count2">0</strong>&nbsp;in queue</span>