fix(watch): ignore nonexistent paths (ENOENT)

Problem:
The `_watch.watch()` strategy may fail if the given path does not exist:

    …/vim/_watch.lua:101: ENOENT: no such file or directory
    stack traceback:
        [C]: in function 'assert'
        …/vim/_watch.lua:101: in function <…/vim/_watch.lua:61>
        [string "<nvim>"]:5: in main chunk

- `_watch.watch()` actively asserts any error returned by `handle:start()`.
- whereas `_watch.watchdirs()` just ignores the result of `root_handle:start()`.

Servers may send "client/registerCapability" with "workspace/didChangeWatchedFiles"
item(s) (`baseUri`) which do not actually exist on the filesystem:
https://github.com/neovim/neovim/issues/28058#issuecomment-2189929424

    {
      method = "client/registerCapability",
      params = {
        registrations = { {
            method = "workspace/didChangeWatchedFiles",
            registerOptions = {
              watchers = { {
                  globPattern = {
                    baseUri = "file:///Users/does/not/exist",
                    pattern = "**/*.{ts,js,mts,mjs,cjs,cts,json,svelte}"
                  }
                },
    ...
    }

Solution:
- Remove the assert in `_watch.watch()`.
- Show a once-only message for both cases.
- More detailed logging is blocked until we have `nvim_log` / `vim.log`.

fix #28058

0 files changed, 0 insertions, 0 deletions