feat(gui): add "Connected since" to the ED2K/Kad Info panes - #650

Mechanical rebase to resolve the po/ catalog conflicts against master's
amule-org#648/amule-org#650/amule-org#651 (per got3nks's note on amule-org#643) -- no source changes here,
scripts/update-po.sh output only, so the diff is just the tree back in
sync with the current strings.

Mechanical rebase to resolve the po/ conflicts against master's
amule-org#643/amule-org#646/amule-org#648/amule-org#650/amule-org#651 -- no source changes here. Confirms got3nks's
prediction on the Alt+<letter>-outside-_() fix: the only genuinely new
msgid in the diff is "Navigate" (the new macOS menu itself); every
other hunk is line-number-comment churn from the rebase, not orphaned
or duplicated translations.

Mechanical rebase to resolve the po/ catalog conflicts against master's
amule-org#648/amule-org#650/amule-org#651 (per got3nks's note on amule-org#643) -- no source changes here,
scripts/update-po.sh output only, so the diff is just the tree back in
sync with the current strings.

* feat(search): persist search history across restarts (#641)

The search field was a plain text control with no memory of past
searches. Swap it for a wxComboBox (a wxTextEntry, like wxTextCtrl,
so the existing GetValue()/Clear() call sites keep working via that
shared base) and persist submitted terms to wxConfig, most-recent
first, capped at 20 entries and deduplicated case-insensitively.

Right-clicking the field opens a small menu ("Remember search
history" checkbox + "Clear search history") so history can be paused
or wiped without a dedicated Preferences page.

i18n: ran scripts/update-po.sh to register the two new menu strings.

* style(search): separate the destructive Clear item from the toggle above

A separator between the checkbox and "Clear search history" keeps the
one-shot destructive action visually distinct from the persistent
on/off state, instead of reading as a second toggle in the same group.

* style(search): use nullptr instead of NULL for the new combo box

Fixes the modernize-use-nullptr clang-tidy finding on the changed
line; matches the nullptr convention already used a couple of
wxComboBox constructions below in the same file.

* feat(search): rework query history per #643 review — file, prefs toggle, edit menu

Addresses all four blocking points from got3nks's review, plus both
optional suggestions:

1. Edit context menu restored. Overriding the field's context menu no
   longer drops Cut/Copy/Paste/Select All -- same custom-Paste-ID idiom
   as CMuleTextCtrl::OnRightDown (wxMenu over-permits wxID_PASTE, so it
   gets a manual clipboard-content check), plus a separator, plus the
   history's own Clear action.

2. Persisted to a dedicated searchhistory.dat (via CTextFile, one term
   per line) instead of amule.conf -- mirrors eMule's AC_SearchStrings.dat.
   Query terms no longer bloat the main config or travel with config
   backups / the --amule-config-file push to amuleweb/amuleapi.

3. "Remember search history" moved into Preferences > General as an
   ordinary Cfg_Bool checkbox (IDC_SEARCHHISTORYENABLED), same
   NewCfgItem wiring as every other GUI-behavior toggle on that page.
   It's a client-side-only setting, so the one checkbox works unchanged
   in both amule and amuleGUI. The context menu keeps only Clear (a
   one-shot action, not a setting to toggle from a hidden menu).

4. Cap raised from 20 to 30, matching eMule's CCustomAutoComplete default.

Optional, done anyway:
- wxComboBox::AutoComplete() wired up (eMule's ACO_AUTOSUGGEST
  equivalent), re-armed after every load/record/clear so it always
  reflects the current entry set.
- Explicitly framed as *query* history throughout (comments, tooltip)
  to distinguish it from the separate, not-yet-implemented result
  persistence that's the rest of #641.

The dedup/move-to-front/cap logic that used to live inline in
CSearchDlg::RecordSearchHistory is extracted into a pure function,
ApplySearchHistoryEntry() (SearchHistory.h/.cpp), decoupled from
wxComboBox/wxConfig specifically so it's unit-testable without a wx
event loop -- new SearchHistoryTest covers empty-list insert, reorder
of an existing term, case-insensitive dedup, empty-term no-op, and
capping (including locking in the actual 30-entry constant).

Rebased onto current master; po/ catalogs regenerated as the final
step so the diff is just the new/changed strings in sync with the tree.

Verified for real: built and ran both amule and amulegui, plus the
full unit test suite (27/27 passing, including the new
SearchHistoryTest's 7 cases).

* fix(tests): link Format.cpp + strerror_r.c into SearchHistoryTest

Same Linux/mingw-only link failure as CMuleCollectionTest/MagnetURITest
already work around: muleunit's MuleDebug.cpp needs CFormat for its
glibc backtrace path, which isn't compiled in on macOS -- so the
target linked fine locally but failed on the Ubuntu/mingw CI builds
(and the clang-tidy jobs, which build the tree first).

* i18n: regenerate po/ catalogs after rebasing onto current master

Mechanical rebase to resolve the po/ catalog conflicts against master's
#648/#650/#651 (per got3nks's note on #643) -- no source changes here,
scripts/update-po.sh output only, so the diff is just the tree back in
sync with the current strings.

* fix(search): avoid an unnamed EReadTextFile bitmask cast in history load

txtIgnoreEmptyLines|txtStripWhitespace has no single named enumerator
to cast to -- clang-tidy Tier-1 flagged it (clang-analyzer-optin.core.
EnumCastOutOfRange), correctly: EReadTextFile isn't a flag enum, so a
synthesized OR'd value is genuinely out of its declared range even
though CTextFile::ReadLines treats it as bitflags at runtime.

txtReadDefault would dodge the cast but also drops '#'-led lines,
silently eating a legitimate search term that happens to start with
one. Read unfiltered (txtReadAll, a real enumerator) and do the
trim/empty-line-drop by hand instead -- same behavior, no cast, no
lost terms.

* i18n: regenerate po/ catalogs after rebasing onto current master

Mechanical rebase to resolve the po/ conflicts against master's #642
(just merged) -- no source changes here.