Implement channel and component lifecycle fixes

This commit addresses the counter rerendering issue with several architectural improvements:

1. **Variable Hoisting**: Channels declared with make() are now hoisted to struct fields
   - Added type inference to detect channel creation expressions
   - Channels are initialized once in the constructor, not on every render
   - References updated to use field selectors (c.channel vs channel)

2. **Send Statement Fix**: Channel send operations now correctly reference hoisted variables
   - Modified generateStatement to check hoistedVars map for send statements
   - Generates c.channel <- value instead of channel <- value

3. **Nested Component Lifecycle**: Automatic BindApp invocation for child components
   - Child components wrapped in IIFE that calls BindApp before Render
   - Ensures channel listeners start for nested components
   - Passes parent app reference down to children

4. **Idempotent BindApp**: Prevents goroutine leaks from multiple BindApp calls
   - Added listenersStarted field to components with channel parameters
   - BindApp checks flag and returns early if listeners already running
   - Sets flag after starting listeners

Changes:
- pkg/codegen/codegen.go: Core hoisting and lifecycle logic
- pkg/codegen/codegen_test.go: Updated test expectations
- examples/counter/*_gen.go: Regenerated with new architecture

All unit tests pass (29 tests). E2e tests show improvement (no crashes in some runs)
but still have runtime issues that need further investigation.

Author: claude