Setting the label `ci:skip-news` will skip the job. This is useful for
maintainers to indicate to contributors that a feature isn't big enough
to warrant a news entry, or for contributors who dislike red CI even if
there's nothing wrong.

Also change label `ci-s390x` to `ci:s390x`; this way it'll be easier to
see that `ci:` are a subcategory of labels that affect CI in some way.

Problem:

The documentation flow (`gen_vimdoc.py`) has several issues:
- it's not very versatile
- depends on doxygen
- doesn't work well with Lua code as it requires an awkward filter script to convert it into pseudo-C.
- The intermediate XML files and filters makes it too much like a rube goldberg machine.

Solution:

Re-implement the flow using Lua, LPEG and treesitter.

- `gen_vimdoc.py` is now replaced with `gen_vimdoc.lua` and replicates a portion of the logic.
- `lua2dox.lua` is gone!
- No more XML files.
- Doxygen is now longer used and instead we now use:
  - LPEG for comment parsing (see `scripts/luacats_grammar.lua` and `scripts/cdoc_grammar.lua`).
  - LPEG for C parsing (see `scripts/cdoc_parser.lua`)
  - Lua patterns for Lua parsing (see `scripts/luacats_parser.lua`).
  - Treesitter for Markdown parsing (see `scripts/text_utils.lua`).
- The generated `runtime/doc/*.mpack` files have been removed.
   - `scripts/gen_eval_files.lua` now instead uses `scripts/cdoc_parser.lua` directly.
- Text wrapping is implemented in `scripts/text_utils.lua` and appears to produce more consistent results (the main contributer to the diff of this change).

Splitting it on word boundaries rather than only spaces allows for better
detection. The issue labeler previously didn't catch titles such as
`treesitter: noisy "Invalid node type" error`.

Co-authored-by: casswedson <casswedson@users.noreply.github.com>

Run the release workflow on macos-14 to use faster M1 runners.

Lock the deployment target to the oldest supported version (11.0,
due to libuv support) instead of relying on the host OS version.

Problem: No test coverage on ARM.

Solution: Add `macos-14` tests, which now run on M1. Skip unit tests as these don't work on M1, see #26145. Also test universal build on M1.

Note: `macos-14` will be `macos-latest` in Q2 2024, so we'll want to switch these to keep Intel and unittest coverage on macos (while GH still offers Intel runners).

Explicitly set the build type for both deps and Nvim. They are already
explicitly set on Windows to RelWithDebInfo. Now also explicitly set
them to Debug on POSIX.

- Consistently use the variable CMAKE_BUILD_TYPE to select build type.
- Remove broken `doc_html` target.
- Remove swap files created by oldtest when cleaning.
- Only rerun `lintdoc` if any documentation files has changed.

Summary: Separate the lint job (`make lintdoc`) to validate runtime/doc,
it is no longer as a part of functionaltest (help_spec).

Build (cmake) and CI:

- `make lintdoc`: validate vimdoc files and test-generate HTML docs.
  CI will run this as a part of the "docs" workflow.

- `scripts/lintdoc.lua` is added as an entry point (executable script)
  for validating vimdoc files.

scripts/gen_help_html.lua:

- Move the tests for validating docs and generating HTMLs from
  `help_spec.lua` to `gen_help_html`. Added:
  - `gen_help_html.run_validate()`.
  - `gen_help_html.test_gen()`.

- Do not hard-code `help_dir` to `build/runtime/doc`, but resolve from
  `$VIMRUNTIME`. Therefore, the `make lintdoc` job will check doc files
  on `./runtime/doc`, not on `./build/runtime/doc`.

- Add type annotations for gen_help_html.

Change the link to point to INSTALL.md.

The contents were moved in https://github.com/neovim/neovim/pull/26533