feat: Replace foliate-js submodule with npm git dependency

Migrate from git submodule to npm package management for better
developer experience and simplified deployment.
Changes:
- Add @bookhoard/foliate-js from GitHub fork
(john-okeefe/foliate-js#bookhoard-panel-detection)
- Update vite alias to point to node_modules instead of vendor
- Delete .gitmodules (no submodules tracked)
- Remove scripts/setup-git-hooks.sh (no longer needed)
- Delete web/vendor/foliate-js/ submodule directory
- Remove sc-commit git alias (submodule-specific)
Benefits:
- Standard npm workflow (npm install / npm update)
- No authentication issues for end users (public GitHub)
- Simpler deployment (npm ci in containers)
- foliate-js protected in node_modules (AI won't rewrite)
- Independent project management
- Cleaner git history
Technical details:
- Import remains unchanged: import "foliate-js/view.js"
- Vite alias maps "foliate-js" to "/node_modules/@bookhoard/foliate-js"
- Build verified working (reader.js includes foliate-js)
- Package installed from git branch: bookhoard-panel-detection

scripts/setup-git-hooks.sh

@@ -1,24 +0,0 @@
-#!/bin/bash
-# One-time setup for git hooks on this machine
-echo "🔒 Installing pre-push safety hook to prevent pushing with uncommitted submodule changes..."
-# Create hooks directory
-mkdir -p .git/hooks
-# Create pre-push hook
-cat >.git/hooks/pre-push <<'EOF'
-#!/bin/bash
-# Prevent pushing if submodules have uncommitted changes
-uncommitted=$(git submodule foreach --quiet 'if [ "$(git status --porcelain)" != "" ]; then echo $name; fi')
-if [ -n "$uncommitted" ]; then
-    echo "❌ ERROR: Submodules have uncommitted changes:"
-    echo "$uncommitted"
-    echo "Commit submodules first (or use git sc-commit)"
-    exit 1
-fi
-EOF
-# Make hook executable
-chmod +x .git/hooks/pre-push
-# Add git alias for submodule commit
-git config --global alias.sc-commit '!sh -c "git submodule foreach \"git add -A && git commit -m \\\"$1\\\" && git push\"" -'
-echo "✅ Git hooks and alias installed!"
-echo "   - Pre-push hook: Checks for uncommitted submodule changes"
-echo "   - Alias: 'git sc-commit' to commit and push all submodules"