YAML Formatter & Converter

This formatter converts in both directions between YAML and JSON only, using the `yaml` npm library (a separate selector for input and output format, plus a swap button that feeds the current output back into the input box). Despite the file being named YamlTomlFormatter, TOML is not supported anywhere in the code: the only two options are YAML and JSON. Parsing runs through `YAML.parse()` for YAML input and the browser's native `JSON.parse()` for JSON, and re-serialization uses `YAML.stringify()` or `JSON.stringify()`. The indent control is limited to exactly two choices, 2 or 4 spaces, and that value is applied to whichever output format you pick. Because YAML is a superset of JSON, the JSON-to-YAML direction is clean, but converting YAML back to JSON collapses everything to the parsed data model, so comments (lines beginning with #) and any anchor/alias structure in the source are not preserved in the JSON output.

Errors are surfaced with precise positioning rather than a generic failure. When `YAML.parse()` throws a `YAML.YAMLParseError`, the tool reads `linePos[0]` to show the exact line and column, renders a 'Line N, Col N' badge, and paints a red highlight bar over the offending line in the input editor (both panes carry a gutter of line numbers). For JSON input it falls back to parsing the native `SyntaxError`, regex-extracting the character offset from the 'position N' message and counting newlines up to that point to report a line number. While the input parses cleanly a green 'Valid YAML to JSON' style banner is shown reflecting the active conversion direction.

A 'Try Auto-Fix' button appears only when the input format is YAML and a parse error is present; it runs a fixed sequence of nine string-level repairs aimed at YAML's most common syntax traps. It converts tabs to two spaces (YAML forbids tabs for indentation outright), inserts the missing space after a colon in key: value pairs and after a list dash, strips trailing whitespace, and rounds each line's leading indentation to the nearest multiple of two. It also drops lines it judges to be garbage (anything two characters or shorter, or without a colon and not a list item or comment), rewrites bare empty inline collections so `key: {}` becomes `key:` and `key: []` stays as an empty array, prepends a `---` document separator when a multi-document marker is detected mid-file, and collapses three or more consecutive blank lines down to one. This is a best-effort heuristic cleaner, not a full reparse, so it can discard content it misclassifies as junk; the parser itself is run with default options, so it does not flag duplicate keys (the `yaml` library keeps the last value rather than erroring), and YAML's type-coercion footguns (unquoted no/off/yes parsing as booleans, leading-zero strings like ZIP codes, or HH:MM sexagesimal numbers) are resolved by the parser, not corrected by auto-fix.