feat(treesitter): add get_captures() for positions and ranges

Problem: get_captures_at_pos() only returns captures at one position. It
cannot query a whole line or range. It can also miss captures from
injected languages outside the visible area.

Solution: Add vim.treesitter.get_captures() with a required start and an
optional exclusive stop. Accept row numbers or {row, col} positions.
Without a stop, query one position or a whole line. Parse the requested
range and return capture coordinates.

Deprecate get_captures_at_pos() with a compatibility wrapper and migrate
its internal callers. Keep get_captures_at_cursor() for capture names at
a window's cursor.

AI-assisted

1 files changed, 18 insertions, 0 deletions

diff --git a/test/functional/plugin/matchparen_spec.lua b/test/functional/plugin/matchparen_spec.lua
index 04a099a36d..30d5b8e62e 100644
--- a/test/functional/plugin/matchparen_spec.lua
+++ b/test/functional/plugin/matchparen_spec.lua
@@ -41,4 +41,22 @@ describe('matchparen', function()
       {1:-- INSERT --}        |
     ]])
   end)
+
+  it('skips treesitter strings in another window', function()
+    api.nvim_buf_set_lines(0, 0, -1, false, { 'print(")")' })
+    n.exec_lua(function()
+      vim.treesitter.start(0, 'lua')
+    end)
+    api.nvim_win_set_cursor(0, { 1, 5 })
+    local win = api.nvim_get_current_win()
+    command('new')
+    eq(
+      { { 1, 6, 1 }, { 1, 10, 1 } },
+      n.exec_lua(function(target_win)
+        require('nvim.matchparen').highlight_matching_pair(target_win)
+        local match = vim.fn.getmatches(target_win)[1]
+        return { match.pos1, match.pos2 }
+      end, win)
+    )
+  end)
 end)