feat: add Alpine.js framework and update build configuration

Add Alpine.js reactive framework for client-side state management, replacing
(window as any) pattern with modern component-based architecture.

Build configuration changes:
- package.json: Update build scripts to use main.ts as entry point
  - Change from web/src/*.ts glob to web/src/main.ts
  - Update all build:ts scripts to use --outfile instead of --outdir
  - Add build and dev scripts for complete build process
- Build now produces single main.js bundle (~120-150KB minified)

Alpine.js setup:
- web/src/alpine.ts: Create Alpine initialization module
  - Extend Window interface with Alpine type declaration
  - Initialize Alpine and attach to window for DevTools
  - Re-export Alpine for other modules to register globals/components

Frontend module updates:
- web/src/main.ts: Import alpine.ts last to initialize framework
- web/src/toast.ts: Add Alpine import (ready for migration to Alpine.global())

Architecture:
- Alpine.js for client-side state (modals, dropdowns, theme switching)
- HTMX for server calls (existing pattern, unchanged)
- Hybrid approach: Alpine reactive components + HTMX form submissions

Next steps (see esbuild-setup.md for detailed guide):
- Migrate TypeScript files from (window as any) to Alpine.global()
- Update 27 templates to use @click instead of onclick
- Add x-data/x-show for stateful UI components

Note: web/src/docs.ts has pending changes with Lunr imports that need
separate handling (data files don't exist yet - backend API search planned,
see DOCS_SEARCH_IMPLEMENTATION.md)

web/src/toast.ts

@@ -1,3 +1,4 @@
+import { Alpine } from "./alpine";
 // Toast notification system for backend errors
 // Displays toast notifications at the top of the page