rebrand to orc-gallery and optimise search/thumbnail responsiveness

Rebrand:
- Rename project, binary, desktop file, and icons from screenshot-gallery/orcs-gallery to orc-gallery
- Update display name to "ORC Gallery" throughout (window title, .desktop, README, plan.md)
- Config dir changed from ScreenshotOCRGallery to OrcGallery

Performance:
- cancelSearch() is now non-blocking; new searches start immediately instead of waiting for the previous thread to drain
- Remove double-emit from QFutureWatcher::finished handler; results emitted once directly from background thread
- SQLite WAL mode + NORMAL sync + 20 MB page cache + memory temp store + 256 MB mmap applied on init and per-thread connections
- Typing inactivity timer reduced from 500 ms to 150 ms
- COUNT(*) OVER() window function folds total-count into the main SELECT, eliminating a separate COUNT round-trip per search
- ImageThumbnail::paintEvent draws the filename overlay; removes 3 child QObjects (QFrame + QLabel + QHBoxLayout) per thumbnail
- loadThumbnailAsync posts QImage load+scale to QThreadPool; QPixmap::fromImage called on main thread via Qt::QueuedConnection invokeMethod; QPointer guards against use-after-free on gallery clear

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

OCR-scripts/direct_rofi_ocr.sh

@@ -4,7 +4,7 @@
 # This script displays OCR data from SQLite and allows opening files with rofi
 
 # Database path
-DB_PATH="${XDG_DATA_HOME:-$HOME/.local/share}/screenshot-gallery/screenshot_ocr.db"
+DB_PATH="${XDG_DATA_HOME:-$HOME/.local/share}/orc-gallery/screenshot_ocr.db"
 
 # Check dependencies
 check_deps() {

OCR-scripts/ocr_rofi.sh

@@ -4,7 +4,7 @@
 # This script displays OCR data from SQLite and allows opening files with rofi
 
 # Database path
-DB_PATH="${XDG_DATA_HOME:-$HOME/.local/share}/screenshot-gallery/screenshot_ocr.db"
+DB_PATH="${XDG_DATA_HOME:-$HOME/.local/share}/orc-gallery/screenshot_ocr.db"
 SCREENSHOTS_DIR="$HOME/Screenshots"
 MAX_TEXT_LENGTH=100
 

OCR-scripts/ocr_screenshots.py

@@ -7,8 +7,8 @@ Usage:
 
 Arguments:
     --db              Path to the SQLite database file.
-                      Default: $XDG_DATA_HOME/screenshot-gallery/screenshot_ocr.db
-                               (~/.local/share/screenshot-gallery/screenshot_ocr.db)
+                      Default: $XDG_DATA_HOME/orc-gallery/screenshot_ocr.db
+                               (~/.local/share/orc-gallery/screenshot_ocr.db)
     --screenshots-dir Directory containing screenshot images to process.
                       Default: ~/Screenshots
 """
@@ -53,7 +53,7 @@ signal.signal(signal.SIGINT,  _handle_signal)
 # ---------------------------------------------------------------------------
 def parse_args() -> argparse.Namespace:
     xdg_data = os.environ.get("XDG_DATA_HOME", os.path.expanduser("~/.local/share"))
-    default_db  = os.path.join(xdg_data, "screenshot-gallery", "screenshot_ocr.db")
+    default_db  = os.path.join(xdg_data, "orc-gallery", "screenshot_ocr.db")
     default_dir = os.path.expanduser("~/Screenshots")
 
     parser = argparse.ArgumentParser(

OCR-scripts/ocr_search_rofi.py

@@ -7,7 +7,7 @@ import sys
 import tempfile
 
 # Configuration
-DB_PATH = os.path.join(os.environ.get("XDG_DATA_HOME", os.path.expanduser("~/.local/share")), "screenshot-gallery", "screenshot_ocr.db")
+DB_PATH = os.path.join(os.environ.get("XDG_DATA_HOME", os.path.expanduser("~/.local/share")), "orc-gallery", "screenshot_ocr.db")
 SCREENSHOTS_DIR = os.path.expanduser("~/Screenshots")
 ROFI_PROMPT = "OCR Search"
 

OCR-scripts/rofi_ocr_search.sh

@@ -4,7 +4,7 @@
 # This script displays OCR'd screenshot data in rofi and allows opening selected files
 
 # Constants
-DATABASE_PATH="${XDG_DATA_HOME:-$HOME/.local/share}/screenshot-gallery/screenshot_ocr.db"
+DATABASE_PATH="${XDG_DATA_HOME:-$HOME/.local/share}/orc-gallery/screenshot_ocr.db"
 SCREENSHOTS_DIR="$HOME/Screenshots"
 ROFI_PROMPT="Screenshot OCR"
 MAX_DISPLAY_LENGTH=100

OCR-scripts/search_ocr.py

@@ -7,7 +7,7 @@ import sys
 from datetime import datetime
 
 # Constants
-DATABASE_PATH = os.path.join(os.environ.get("XDG_DATA_HOME", os.path.expanduser("~/.local/share")), "screenshot-gallery", "screenshot_ocr.db")
+DATABASE_PATH = os.path.join(os.environ.get("XDG_DATA_HOME", os.path.expanduser("~/.local/share")), "orc-gallery", "screenshot_ocr.db")
 
 
 def parse_arguments():

OCR-scripts/simple_rofi_ocr.sh

@@ -3,7 +3,7 @@
 # simple_rofi_ocr.sh - A simplified script to search OCR'd screenshots with rofi
 
 # Database location
-DB_PATH="${XDG_DATA_HOME:-$HOME/.local/share}/screenshot-gallery/screenshot_ocr.db"
+DB_PATH="${XDG_DATA_HOME:-$HOME/.local/share}/orc-gallery/screenshot_ocr.db"
 
 # Check if database exists
 if [ ! -f "$DB_PATH" ]; then