tweaks

1. utils/weather_sat.py — Added delete_all_images() method that globs for *.png, *.jpg, *.jpeg in the output dir, unlinks each, clears _images list, and returns the
  count.
  2. routes/weather_sat.py — Added DELETE /weather-sat/images route that calls decoder.delete_all_images() and returns {'status': 'ok', 'deleted': count}.
  3. static/js/modes/weather-satellite.js:
    - Added currentModalFilename state variable
    - renderGallery() now sorts images by timestamp descending, groups by date using toLocaleDateString(), renders date headers spanning the grid, and adds a delete
  overlay button on each card
    - showImage() accepts a filename param, stores it in currentModalFilename, and creates a modal toolbar with a delete button
    - Added deleteImage(filename) — confirm dialog → DELETE /weather-sat/images/{filename} → filter from array → re-render + close modal
    - Added deleteAllImages() — confirm dialog → DELETE /weather-sat/images → clear array → re-render
    - Exposed deleteImage, deleteAllImages, and _getModalFilename in public API
  4. static/css/modes/weather-satellite.css:
    - Added position: relative to .wxsat-image-card
    - .wxsat-image-actions — absolute top-right overlay, hidden by default, appears on card hover
    - .wxsat-image-actions button — dark background, turns red on hover
    - .wxsat-date-header — full-grid-width date separator with dimmed uppercase text
    - .wxsat-modal-toolbar — absolute top-left in modal for the delete button
    - .wxsat-modal-btn.delete — turns red on hover
    - .wxsat-gallery-clear-btn — subtle icon button, pushed right via margin-left: auto, turns red on hover
    - Updated .wxsat-gallery-header from justify-content: space-between to gap: 8px for proper 3-child layout
  5. templates/index.html — Added clear-all trash button with SVG icon in the gallery header, wired to WeatherSat.deleteAllImages().

static/css/modes/weather-satellite.css

@@ -530,7 +530,7 @@
 .wxsat-gallery-header {
     display: flex;
     align-items: center;
-    justify-content: space-between;
+    gap: 8px;
     padding: 10px 14px;
     background: var(--bg-tertiary, #1a1f2e);
     border-bottom: 1px solid var(--border-color, #2a3040);
@@ -561,6 +561,7 @@
 }
 
 .wxsat-image-card {
+    position: relative;
     background: var(--bg-primary, #0d1117);
     border: 1px solid var(--border-color, #2a3040);
     border-radius: 6px;
@@ -575,6 +576,43 @@
     box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
 }
 
+.wxsat-image-clickable {
+    display: block;
+}
+
+.wxsat-image-actions {
+    position: absolute;
+    top: 6px;
+    right: 6px;
+    opacity: 0;
+    transition: opacity 0.2s;
+    z-index: 2;
+}
+
+.wxsat-image-card:hover .wxsat-image-actions {
+    opacity: 1;
+}
+
+.wxsat-image-actions button {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    width: 28px;
+    height: 28px;
+    padding: 0;
+    border: none;
+    border-radius: 4px;
+    background: rgba(0, 0, 0, 0.7);
+    color: var(--text-secondary, #999);
+    cursor: pointer;
+    transition: all 0.2s;
+}
+
+.wxsat-image-actions button:hover {
+    background: rgba(255, 68, 68, 0.9);
+    color: #fff;
+}
+
 .wxsat-image-preview {
     width: 100%;
     aspect-ratio: 4/3;
@@ -607,6 +645,23 @@
     margin-top: 2px;
 }
 
+/* Date group headers */
+.wxsat-date-header {
+    grid-column: 1 / -1;
+    font-size: 11px;
+    font-family: 'JetBrains Mono', monospace;
+    color: var(--text-dim, #666);
+    text-transform: uppercase;
+    letter-spacing: 0.5px;
+    padding: 8px 0 4px;
+    border-bottom: 1px solid var(--border-color, #2a3040);
+    margin-bottom: 4px;
+}
+
+.wxsat-date-header:first-child {
+    padding-top: 0;
+}
+
 /* Empty state */
 .wxsat-gallery-empty {
     display: flex;
@@ -734,6 +789,56 @@
     text-align: center;
 }
 
+.wxsat-modal-toolbar {
+    position: absolute;
+    top: 16px;
+    left: 24px;
+    z-index: 10001;
+    display: flex;
+    gap: 8px;
+}
+
+.wxsat-modal-btn {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    width: 36px;
+    height: 36px;
+    padding: 0;
+    border: 1px solid rgba(255, 255, 255, 0.2);
+    border-radius: 6px;
+    background: rgba(0, 0, 0, 0.6);
+    color: var(--text-secondary, #999);
+    cursor: pointer;
+    transition: all 0.2s;
+}
+
+.wxsat-modal-btn.delete:hover {
+    background: rgba(255, 68, 68, 0.9);
+    border-color: #ff4444;
+    color: #fff;
+}
+
+/* Gallery clear-all button */
+.wxsat-gallery-clear-btn {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    margin-left: auto;
+    padding: 4px;
+    border: none;
+    border-radius: 4px;
+    background: transparent;
+    color: var(--text-dim, #666);
+    cursor: pointer;
+    transition: all 0.2s;
+}
+
+.wxsat-gallery-clear-btn:hover {
+    color: #ff4444;
+    background: rgba(255, 68, 68, 0.1);
+}
+
 /* ===== Responsive ===== */
 @media (max-width: 1100px) {
     .wxsat-content {