[GIT PULL] gitk: Sync with 2.50.1, Tcl >= 8.6, git >= 2.20

Many of the commits listed below are already in git.git via v2.50.1.
Additionally, with this version, we require more modern Tcl/Tk and Git.
New features are:
- Refs in the refs dialog are sorted by kind (local, upstream remote,
  other remote, tags, other refs).
- SHA256 repositories are supported.

The following changes since commit bfb0fa7099e541c15d103b75f453f613a751da03:

  Merge branch 'top-panel-search-highlight' of github.com:bnfour/gitk (2025-05-22 19:15:31 +0200)

are available in the Git repository at:

  https://github.com/j6t/gitk.git master

for you to fetch changes up to 2d3f3f01270a47bed15db774b577b22a9c9c8d9e:

  gitk: remove header of now empty section "General options" (2025-07-22 18:34:21 +0200)

----------------------------------------------------------------
Avi Halachmi (:avih) (1):
      gitk: encode arguments correctly with "open"

Johannes Sixt (20):
      gitk: treat file names beginning with "|" as relative paths
      gitk: have callers of diffcmd supply pipe symbol when necessary
      gitk: sanitize 'exec' arguments: simple cases
      gitk: sanitize 'exec' arguments: 'eval exec'
      gitk: sanitize 'exec' arguments: redirections
      gitk: sanitize 'exec' arguments: redirections and background
      gitk: sanitize 'exec' arguments: redirect to process
      gitk: sanitize 'open' arguments: simple commands
      gitk: sanitize 'open' arguments: simple commands with redirections
      gitk: sanitize 'open' arguments: simple commands, readable and writable
      gitk: collect construction of blameargs into a single conditional
      gitk: sanitize 'open' arguments: command pipeline
      gitk: sanitize 'open' arguments: revisit recently updated 'open' calls
      Merge branch 'ah/fix-open-with-stdin'
      Merge branch 'js/fix-open-exec'
      gitk: choosefont - remove a stray debugging line
      Merge branch 'ti/support-sha256'
      Merge branch 'mr/sort-refs-by-type'
      Merge branch 'ml/abandon-old-version' (early part)
      gitk: remove header of now empty section "General options"

Mark Levedahl (15):
      gitk: require git >= 2.20
      gitk: remove code targeting git <= 1.7.2
      gitk: Make TclTk 8.6 the minimum, allow 8.7
      gitk: remove implementations for Tcl/Tk < 8.6
      gitk: use $config_variables as list for save/restore
      gitk: always use themed Tk (ttk)
      gitk: replace ${NS} with ttk
      gitk: remove non-ttk support code
      gitk: separate x11 / win32 / aqua Mouse bindings
      gitk: wheel scrolling multiplier preference
      gitk: mousewheel scrolling functions for Tk 8.6
      gitk: update win32 scrolling for Tk 8.6 / TIP 171
      gitk: update x11 scrolling for TclTk 8.6 / TIP 171
      gitk: update aqua scrolling for TclTk 8.6 / TIP171
      gitk: allow horizontal commit-graph scrolling

Michael Rappazzo (3):
      gitk: sort by ref type on the 'tags and heads' view
      gitk: make 'sort-refs-by-type' optional and persistent
      gitk: separate upstream refs when using the sort-by-type option

Takashi Iwai (1):
      gitk: Add support of SHA256 repositories

Taylor Blau (1):
      Merge branch 'js/fix-open-exec-2.40.0' into js/fix-open-exec

 gitk | 1405 ++++++++++++++++++++++++++++++++----------------------------------
 1 file changed, 671 insertions(+), 734 deletions(-)