Problem:
`vim.fs.slug()` does not handle URIs like `term://foo//123:bash`,
so callers (e.g. terminal persistence) must strip the scheme before
calling `slug()`.
Solution:
Detect `scheme://` from the raw input before `normalize()` and
replace it with a `=uri-<scheme>-` prefix.
Problem:
Several subsystems need to derive a short, filesystem-safe identifier from an
arbitrary path, and each reinvents it ad-hoc:
- `'undodir'` and `swapfiles` encode the full path into a single filename, which
may exceed filesystem length-limits.
- `:connect ssh://` needs the SSH ControlPath socket name to stay under the
104-byte `sun_path` limit on macOS; today the path overflows it.
- the upcoming :terminal state dir.
- arbitrary plugin purposes.
Solution:
Provide `vim.fs.slug()`, which generates a bounded, one-way filename from an
arbitrary string. The input is normalized so equivalent paths produce the
same result. An 8-char hash is appended for uniqueness
Problems:
On Windows, `:w somedir` (where somedir is an existing directory
in pwd) shows the misleading `E13: File exists (add ! to override)`
instead of `E17: "somedir" is a directory`.
Solution:
drop unnecessary `#ifdef` guard.
Problem:
The temp_dict in `do_autocmd_progress()` is sized 7, but the max is 6 (id, text, percent, status, title, data). The extra capacity is rather misleading.
Solution:
make the size of the dict 6.