Add Apple Pencil support, reading plan, full-text search, and inline ink

- Apple Pencil hover cursor: previews brush size/shape before contact
- Tilt shading: tilted pen strokes widen and reduce thinning via tiltX/Y
- Two-finger undo in draw mode (non-stylus two-finger tap)
- Copy & open Claude buttons: copies study/podcast prompt then opens claude.ai/new
- Inline ink canvas in study notes (DrawCanvas embedded in Notes tab)
- Full-text search across all project notes with 300ms debounce
- Reading plan: set a book + week goal, mark chapters read from the reader

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

src/pages/StudyPage.jsx

@@ -515,6 +515,29 @@ export default function StudyPage() {
                   </datalist>
                 </div>
 
+                {/* Inline ink notes — collapsible, always available without switching to annotate mode */}
+                <div className={`rounded-3xl border border-slate-200 bg-slate-50 p-5 ${mobileStudyTab !== 'notes' ? 'max-sm:hidden' : ''} ${studyLayout === 'split' && activeStudyTab !== 'notes' ? 'hidden' : ''}`}>
+                  <button
+                    type="button"
+                    onClick={() => setCollapsedSections((c) => ({ ...c, inlineInk: !c.inlineInk }))}
+                    className="flex w-full items-center justify-between gap-2 text-left"
+                  >
+                    <div>
+                      <h3 className="text-sm font-semibold text-slate-900">Ink Notes</h3>
+                      <p className="text-xs text-slate-500">Draw diagrams or handwritten notes for this chunk.</p>
+                    </div>
+                    <span className="text-slate-400">{collapsedSections.inlineInk ? '▸' : '▾'}</span>
+                  </button>
+                  {!collapsedSections.inlineInk && (
+                    <div className="mt-4">
+                      <DrawCanvas
+                        strokes={selectedChunk.inkStrokes ?? []}
+                        onStrokesChange={(s) => updateChunk(selectedChunk.id, { inkStrokes: s })}
+                      />
+                    </div>
+                  )}
+                </div>
+
                 {/* Cross-references */}
                 <div className={`rounded-3xl border border-slate-200 bg-slate-50 p-5 ${mobileStudyTab !== 'crossRefs' ? 'max-sm:hidden' : ''} ${studyLayout === 'split' && activeStudyTab !== 'crossRefs' ? 'hidden' : ''}`}>
                   <button