* Implement support for generating clangd `compile_commands.json` config
* Add example .clangd file
* Tidy .gitignore and add entries for clangd and other things
* couple things i forgot to remove
* Change indent level to 2
* Centralize file type checking logic
* Refactor flag replacments to fix `-lang=` flags not being handled
* Move language flag fallback addition to `generate_build_ninja`
* Remove file type flags from .clangd example
* Remove clangd compiler defines option
Projects which need it can define things themselves in .clangd
* Move global clangd flags to tools/project.py & update vscode config
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Co-authored-by: Luke Street <luke@street.dev>