fix: multi-TG export wire names lose TG identity under shortening

[pskillen]

Problem

When a logical channel fans out via multi-talkgroup expansion (#36) and export name shortening is enabled (#130), sibling rows from the same repeater collapse to identical wire names (GL Glas, GL Glas 2, …). Talk-group identity survives only in the Contact column — not on the radio LCD channel name.

Root cause: expandTalkGroupsForExport appends {row.wireName} {memberName} then generic shortening truncates the TG suffix; uniqueWireName adds meaningless numeric disambiguators.

Intended fix

TG-aware export name composition modes (default: callsign_tg_abbrev e.g. GB7GL Sco TS2), with failsafe suffix_tg_number using TalkGroup.number (+ /ts when timeslotOverride set).

Related

• feat: multi-talkgroup channels (denormalise one channel into repeater × talkgroup pairs on export) #36 — multi-talkgroup expansion
• Exported channel names from m×n expansion overflow tight radio LCD limits #130 — export name shortening
• feat: Channel.abbreviation for export name shortening (name qualifier only) #150 — Channel.abbreviation