fix(log): mark a held clock in words, not only in colour

Three corrections to the editable-time commit.

The held clock was distinguished only by colorScheme.primary. Material is explicit that
colour must not be the sole carrier of meaning, and roughly one man in twelve cannot
reliably separate that colour from the default text. Missing it costs every remaining
contact the wrong time and, for a pass across midnight UTC, the wrong day. The row now reads
"Held at 23:58" rather than just showing it in a different colour.

The comment on the state claimed rememberSaveable survives rotation but not process death.
Official documentation says the opposite: it goes through the saved instance state and does
survive system-initiated process death. A probe traced the one case that genuinely loses the
hold - the user swiping the app away - and not restoring it there is correct, since a clock
pressed hours ago would put the next session's contacts on the wrong day. The comment says
that now instead of something false.

MenuAnchorType is deprecated in favour of ExposedDropdownMenuAnchorType. Surfaced by a
subagent's build log rather than mine, because my grep filter was hiding warnings.

core/presentation/src/main/res/values-zh/strings.xml

@@ -280,6 +280,7 @@
     <string name="wavelog_mode_edit">修改模式</string>
     <string name="wavelog_time_hint">时间</string>
     <string name="wavelog_time_live">当前</string>
+    <string name="wavelog_time_held">按住 %1$s</string>
     <string name="wavelog_time_edit">设置记录时间</string>
     <string name="wavelog_time_help">UTC 时间如 14:55, 或 +3 / -2 分钟。留空则用当前时间。</string>
     <string name="wavelog_time_unrecognised">不是时间 - 将使用当前时间</string>

core/presentation/src/main/res/values/strings.xml

@@ -311,6 +311,7 @@
     <string name="wavelog_mode_edit">Edit the mode</string>
     <string name="wavelog_time_hint">Time</string>
     <string name="wavelog_time_live">Now</string>
+    <string name="wavelog_time_held">Held at %1$s</string>
     <string name="wavelog_time_edit">Set the logging time</string>
     <string name="wavelog_time_help">UTC time such as 14:55, or +3 / -2 minutes. Empty logs at the current time.</string>
     <string name="wavelog_time_unrecognised">Not a time - the current time will be used</string>