Extend CapturedEnv to include function parameters used in loop conditions,
enabling ExprLowerer to resolve variables like `s` in `loop(p < s.length())`.
Phase 245C changes:
- function_scope_capture.rs: Add collect_names_in_loop_parts() helper
- function_scope_capture.rs: Extend analyze_captured_vars_v2() with param capture logic
- function_scope_capture.rs: Add 4 new comprehensive tests
Test fix:
- expr_lowerer/ast_support.rs: Accept all MethodCall nodes for syntax support
(validation happens during lowering in MethodCallLowerer)
Problem solved: "Variable not found: s" errors in loop conditions
Test results: 924/924 PASS (+13 from baseline 911)
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
