v1.8.14: Tool parser regex recovery, JSON leak fix, tool UI flatten, unquoted value fix, CSS content leak guard

- toolParser.js: Regex-based recovery when tryParseJson fails on balanced JSON (handles huge HTML/CSS in write_file content)
- toolParser.js: fixQuoting now handles unquoted Windows path values
- chatContentParser.ts: Extended JSON leak suppression - skip window extends past leaked content when brace counter gives premature endIdx
- chatContentParser.ts: stripToolArtifacts strips bulk CSS/HTML leaked from truncated write_file continuations
- ChatWidgets.tsx: Tool labels now italicized, ToolCallGroup flattened (always-visible individual blocks, no master dropdown)

Author: Brendan Gray