feat(photo-editor): Ajax Image Editor client (Photoshop-parity tools)

Photoshop-parity editor client: layers, selection/masking, brushes,
smart filters, LUT import, Quick Edit, mobile gestures, workspaces,
batch operations, and the service-worker versioning (v978->v1006).

Source: vendor/photocraft (ad1cff44) photo-editor client files, merged
onto upstream/dev (a8c147b2). Conflict resolution documented in
pr_work/A_conflicts.md; editor files taken from vendor/photocraft
(upstream's editor is an earlier snapshot of the same feature).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/test_editor_quick_edit_invert.py

@@ -0,0 +1,37 @@
+"""Quick Edit can colour-invert the image (Photoshop Image ▸ Adjustments ▸ Invert).
+
+Photoshop's Invert (Cmd/Ctrl+I) colour-inverts the active layer. The command box
+had no handling for it, so "invert the colours" was swallowed by the Select ▸
+Inverse branch and inverted the *selection* instead. It now routes to the real
+`invert` adjustment before the selection block, while "invert the selection"
+still reaches Select ▸ Inverse.
+"""
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[1]
+EDITOR = (ROOT / "static" / "js" / "galleryEditor.js").read_text(encoding="utf-8")
+ADJ = (ROOT / "static" / "js" / "editor" / "fx" / "adj-popup.js").read_text(encoding="utf-8")
+COVERAGE = (ROOT / "docs" / "QUICKEDIT_COVERAGE.md").read_text(encoding="utf-8")
+
+
+def test_invert_routing_present():
+    assert r"if (/\binvert\b[^.]*\b(?:colou?rs?|tones?|image|photo|picture)\b/.test(p)" in EDITOR
+    assert r"|| /\b(?:colou?rs?|image|photo|picture)\b[^.]*\binvert\b/.test(p)) {" in EDITOR
+    assert "await _runQuickControlOp('adjustments.apply', { type: 'invert' });" in EDITOR
+    assert "'Inverted the colours.'" in EDITOR
+
+
+def test_routing_precedes_selection_invert():
+    routing = EDITOR.index("await _runQuickControlOp('adjustments.apply', { type: 'invert' });")
+    assert routing < EDITOR.index("// --- Selection commands (deterministic, no model call) ---")
+    assert routing < EDITOR.index("await _runQuickControlOp('selection.invert', {});")
+
+
+def test_invert_adjustment_is_supported():
+    assert "{ type: 'invert'," in ADJ
+
+
+def test_coverage_doc_marks_invert_ok():
+    row = next(line for line in COVERAGE.splitlines() if "Adjustments → Invert" in line)
+    assert "OK" in row
+    assert "fast path" in row