feat(sidebarLeft): add pinboard widget for pinned notes & images

[FierraCodes]

Summary

Adds a new Pinboard tab to the left sidebar for storing, organizing, and browsing pinned notes and images.

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Features

• Sidebar Tab Integration: Adds a Pinboard tab with push_pin icon and sidebar configuration toggle (Config.options.sidebar.pinboard.enable).
• Bottom Compose Card:
  • Multi-line text input with Ctrl+Enter to pin and Ctrl+V clipboard paste.
  • Image picker dialog (supports Zenity / KDialog).
  • Smart clipboard paste: auto-detects copied images or text and attaches them.
• Responsive Image Scaling: Pinned images dynamically scale to the full sidebar width while preserving their native aspect ratios.
• Draggable Reordering:
  • Dedicated 6-dot vertical drag handle (drag_indicator) on the left of each card.
  • Smooth card displacement animations with elevated highlight state.
  • Edge Auto-Scrolling: Continuously auto-scrolls the list when dragging cards near or beyond the top/bottom viewport edges.
• Item-by-Item Browsing:
  • Top navigation bar showing current item index (Pin N of M) with previous/next scroll buttons.
  • Smooth snap-to-item scrolling with mouse wheel support.
• Card Actions:
  • One-click copy text/image to clipboard with visual feedback.
  • Open images in default external viewer (xdg-open).
  • Delete X button on the top-right of each card.
• Clear All: Bottom summary bar with pinned item counter and a one-click "Clear all" button.
  -Persistence: Backed by services/Pinboard.qml using FileView JSON storage (~/.local/state/quickshell/user/pinboard.json) and persistent image cache (pinboard_images/).

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Changed / Added Files

• services/Pinboard.qml (new): Singleton service managing JSON persistence, file operations, and item reordering.
• modules/ii/sidebarLeft/PinboardWidget.qml (new): Main UI container with compose card, navigation header, auto-scrolling ListView, and clear bar.
• modules/ii/sidebarLeft/pinboard/PinboardItem.qml (new): Individual pinned item card with dynamic image scaling and left drag handle.
• modules/ii/sidebarLeft/SidebarLeftContent.qml: Integrated Pinboard tab and page into the sidebar's SwipeView.
• modules/common/Directories.qml: Added pinboardPath and pinboardImages directories.
• modules/common/Config.qml: Added sidebar.pinboard config options.