Problem:

Capability register logic is spread across 3 files.

Solution:

- Consolidate (and simplify) logic into the client.
- Teach client.supports_method about resolve methods

Previously the LSP-Client object contained some fields that are also
in the client config, but for a lot of other fields, the config was used
directly making the two objects vaguely entangled with either not having
a clear role.

Now the config object is treated purely as config (read-only) from the
client, and any fields the client needs from the config are now copied
in as additional fields.

This means:
- the config object is no longet normalised and is left as the user
  provided it.
- the client only reads the config on creation of the client and all
  other implementations now read the clients version of the fields.

In addition, internal support for multiple callbacks has been added to
the client so the client tracking logic (done in lua.lsp) can be done
more robustly instead of wrapping the user callbacks which may error.

Problem:
  The LSP client code is implemented as a complicated closure-class
  (class defined in a single function).

Solution:
  Move LSP client code to a more conventional Lua class and move to a
  separate file.

The benefit of this is that users only pay for what they use. If e.g.
only `vim.lsp.buf_get_clients()` is called then they don't need to load
all modules under `vim.lsp` which could lead to significant startuptime
saving.

Also `vim.lsp.module` is a bit nicer to user compared to
`require("vim.lsp.module")`.

This isn't used for some nested modules such as `filetype` as it breaks
tests with error messages such as "attempt to index field 'detect'".
It's not entirely certain the reason for this, but it is likely it is
due to filetype being precompiled which would imply deferred loading
isn't needed for performance reasons.

Use the get_language_id client option to resolve the filetype when
matching the document selector in a dynamic capability.


Co-authored-by: Mathias Fussenegger <f.mathias@zignar.net>

refactor(lsp): move glob parsing to vim.glob

Moving the logic for using vim.lpeg to create a match pattern from a
glob into `vim.glob`. There are several places in the LSP spec that
use globs, and it's very useful to have glob matching as a
generally-available utility.

- `client.dynamic_capabilities` is an object that tracks client register/unregister
- `client.supports_method` will additionally check if a dynamic capability supports the method, taking document filters into account. But only if the client enabled `dynamicRegistration` for the capability
- updated the default client capabilities to include dynamicRegistration for:
    - formatting
    - rangeFormatting
    - hover
    - codeAction
    - hover
    - rename