* feat(lua): vim.tbl_contains supports general tables and predicates
Problem: `vim.tbl_contains` only works for list-like tables (integer
keys without gaps) and primitive values (in particular, not for nested
tables).
Solution: Rename `vim.tbl_contains` to `vim.list_contains` and add new
`vim.tbl_contains` that works for general tables and optionally allows
`value` to be a predicate function that is checked for every key.
Whenever we run fs_stat() on a path, save this information in the loader
so it can be re-used.
- Loader.loadfile: Remove arguments `hash` as it is no longer needed.
- Loader.loader: Use _G.loadstring instead of Loader.load
This allows plugins to wrap loadstring to inspection and profiling
- factor out read file logic
