Add GPU/macvlan passthrough, container edit/update, image prune/tag

Create Container form:
- GPU passthrough dropdown (AMD/Intel via /dev/dri detection, NVIDIA
  excluded since it needs a different runtime) - device paths strictly
  validated server-side against the host's own detected list.
- Macvlan network support: selecting a macvlan network reveals a static
  IP field and hides port mappings (meaningless once the container has
  its own LAN address), matching Unraid Docker Manager's "Custom: br0"
  behavior. Networks panel gained a matching macvlan network-creation
  flow, with the parent-interface dropdown read from Unraid's own
  network.cfg so it lists exactly what Docker Manager itself offers.

Containers panel:
- Edit: reopens the create form pre-filled from the container's current
  config (image/ports/volumes/env/network/restart policy/GPU/static IP);
  saving stops+removes the old container and recreates it under the same
  settings, since podman/Docker have no in-place "modify" API for most of
  this.
- Update: same stop/remove/recreate flow, but pulls the current image
  first. "Check for Updates" compares each in-use image's local digest
  against its origin registry (Docker Hub/GHCR/self-hosted registries all
  verified live) with no podman-side feature backing it - implemented via
  the registry's own HTTP API. A small log-modal shows progress for both
  actions instead of a silent wait.
- Fixed a real bug hit live: PodmanClient's flat 15s HTTP timeout aborted
  real image pulls/container creates mid-request; bumped to 600s (nginx
  already allows up to 640s for this plugin's requests).

Images panel:
- "Prune unused" (removes every image with zero containers referencing
  it, not just dangling ones - confirmation copy says so explicitly since
  this is more aggressive than it sounds) and per-image "Tag".

Also several real UI bugs found via live screenshots: unused-image prune
having no visible effect until reloaded, table action-button columns
drifting row to row (a bare "display:flex" on a <td> was fighting the
table layout algorithm), Templates category badges dumping raw multi-tag
strings from real Unraid templates, and low-contrast search/filter
controls that were nearly invisible against the card background.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

webui/plugins/podman/Podman.page

@@ -86,11 +86,13 @@ function podman_asset_version(string $relPath): string
       <div class="podman-card">
         <div class="podman-toolbar">
           <input class="podman-search" id="containers-search" type="text" placeholder="Search containers by name or image…">
-          <div class="filterset" id="containers-filterset" style="display:flex; gap:4px; background:var(--surface-2); padding:3px; border-radius:8px;">
+          <div class="podman-segmented" id="containers-filterset">
             <button class="active" data-filter="all" id="containers-count-all">All</button>
             <button data-filter="running" id="containers-count-running">Running</button>
             <button data-filter="stopped" id="containers-count-stopped">Stopped</button>
           </div>
+          <button class="podman-btn podman-btn-primary" id="containers-check-updates-btn" style="margin-left:auto;">Check for Updates</button>
+          <button class="podman-btn podman-btn-primary" id="containers-update-all-btn">Update All</button>
           <button class="podman-btn podman-btn-primary" id="containers-create-btn">+ New Container</button>
         </div>
         <div class="podman-table-wrap">
@@ -113,6 +115,7 @@ function podman_asset_version(string $relPath): string
       <div class="podman-card">
         <div class="podman-toolbar">
           <input class="podman-search" type="text" placeholder="Search images…" disabled title="Client-side filtering not yet wired up for Images">
+          <button class="podman-btn" id="images-prune-btn" style="margin-left:auto;">Prune unused</button>
           <button class="podman-btn" id="images-pull-btn">&#11015; Pull Image</button>
         </div>
         <div class="podman-table-wrap">
@@ -167,7 +170,7 @@ function podman_asset_version(string $relPath): string
           <div>
             <div class="podman-toolbar">
               <input class="podman-search" id="logs-filter" type="text" placeholder="Filter log output…" style="max-width:280px;">
-              <span id="logs-follow-toggle" style="display:flex; gap:4px; background:var(--surface-2); padding:3px; border-radius:8px;">
+              <span class="podman-segmented" id="logs-follow-toggle">
                 <button class="active" data-follow="true">Follow</button>
                 <button data-follow="false">Paused</button>
               </span>