feature/go-rewrite : base Go avec walk GUI

- Rewrite complet en Go : exe unique sans _internal/, sans extraction temp
- GUI Windows-native via github.com/lxn/walk (TableView, TextEdit, PushButton)
- Meme fonctionnalites : check repos, pull, checkout, auto-update, logs
- build.bat : go build -ldflags "-H windowsgui -s -w" -> 9.6 Mo, zero dependance

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

_internal/_tcl_data/msgs/ms.msg

@@ -1,47 +0,0 @@
-# created by tools/loadICU.tcl -- do not edit
-namespace eval ::tcl::clock {
-    ::msgcat::mcset ms DAYS_OF_WEEK_ABBREV [list \
-        "Aha"\
-        "Isn"\
-        "Sei"\
-        "Rab"\
-        "Kha"\
-        "Jum"\
-        "Sab"]
-    ::msgcat::mcset ms DAYS_OF_WEEK_FULL [list \
-        "Ahad"\
-        "Isnin"\
-        "Selasa"\
-        "Rahu"\
-        "Khamis"\
-        "Jumaat"\
-        "Sabtu"]
-    ::msgcat::mcset ms MONTHS_ABBREV [list \
-        "Jan"\
-        "Feb"\
-        "Mac"\
-        "Apr"\
-        "Mei"\
-        "Jun"\
-        "Jul"\
-        "Ogos"\
-        "Sep"\
-        "Okt"\
-        "Nov"\
-        "Dis"\
-        ""]
-    ::msgcat::mcset ms MONTHS_FULL [list \
-        "Januari"\
-        "Februari"\
-        "Mac"\
-        "April"\
-        "Mei"\
-        "Jun"\
-        "Julai"\
-        "Ogos"\
-        "September"\
-        "Oktober"\
-        "November"\
-        "Disember"\
-        ""]
-}