fix: QA sweep — 7 bugs fixed, 17 test corrections

Code fixes:
- Sidebar state bleed: reset file store on HomePage mount
- restore-photo: raise error instead of silently skipping colorize
  when DDColor model missing
- PaddleOCR OOM: cap input images to 2048px before OCR inference
- Torch CPU optimization: use --index-url .../whl/cpu on CPU nodes

Test fixes:
- upscale: add exact:true to scale factor button locators
- smart-crop: add exact:true to "Pad to square" locator
- colorize: use regex for model button names (Best/Balanced/Fast)
- enhance-faces: use .first() for ambiguous percentage display
- passport-photo: fix DPI locator, .or() compound, generate fallback
- people: update maxUsers assertions for unlimited (0) default
- automate: "Save Pipeline" → "Save" matching actual button text
- tools.test: add resize to Sharp mock chain for OCR tests

tests/unit/ai/tools.test.ts

@@ -4,6 +4,7 @@ import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 // Mock sharp before any imports that use it
 vi.mock("sharp", () => {
   const mockSharp = vi.fn(() => ({
+    resize: vi.fn().mockReturnThis(),
     png: vi.fn().mockReturnThis(),
     jpeg: vi.fn().mockReturnThis(),
     toBuffer: vi.fn().mockResolvedValue(Buffer.from("mock-png-data")),