Exported channel names from m×n expansion overflow tight radio LCD limits

[pskillen]

Problem

When a logical channel expands into multiple CPS rows at export — multi-mode (#46, shipped) and multi-talkgroup (#36) — the generated channel name is composed from the operator's base channel name plus a mode suffix (-F/-D) and/or an appended talkgroup name, e.g. GB7AC Largs Scot West TS1 (25 chars).

Many target radios have very tight LCD name limits (often 11, 13, or 16 characters). The structurally-correct expanded export is therefore frequently unusable: the names are far too long for the radio, and at the tightest limits there is barely room for <callsign> + <place>, let alone an appended talkgroup. Operators currently have to hand-abbreviate names, which pollutes the canonical (vendor-neutral) channel name.

Today the export length limit is only used to emit a warning — names are never actually shortened — and the expanded names are also written verbatim into zone member references, so any shortening must stay consistent across channels and zones.

This is intended as a stop-gap ahead of export profiles (#122), which will own per-profile display-name overrides and profile-aware validation long term. Even after #122, the ability to auto-generate sensible short names for profiled export channels is desirable.

Impact

• Expanded codeplugs cannot be flashed without manual editing on radios with short name limits.
• Pressure to shorten the canonical channel name, undermining vendor neutrality.
• A separate concern: once names are abbreviated/truncated at export, they no longer reverse cleanly on re-import, so the merge-collapse that relies on name stems breaks.

Potential solutions (to be explored, not prescriptive)

• Automatic, generic name shortening to a fixed target length, applied at export inside the channel-expansion layer (so channels and zone members stay consistent). Possible techniques: a curated progressive abbreviation dictionary (e.g. Scotland → Scot → Sco), generic vowel-squeezing, and hard truncation as a last resort, with collision-safe disambiguation.
• Component-level shortening that respects operator intent before generic heuristics, e.g. a first-class TalkGroup.abbreviation field and an amateur-radio callsign-suffix convention (GB7GL → GL).
• Operator-selectable export-time options (target length, callsign-suffix, etc.), with preferences persisted locally.
• Reusable shortening helpers so a future "Generate short name" action can apply the same rules once radio profiles (feat: export profiles on codeplug project #122) ship.
• Relaxing/loosening re-import matching so abbreviated names still re-merge — potentially moving toward a score-based match across name, frequency, location, colour code, timeslot, and mode rather than name alone. (A thorough score-based matcher likely warrants its own ticket.)

Related

• feat: export profiles on codeplug project #122 — export profiles / per-profile display-name overrides (long-term owner)
• feat: support for multi-mode channels #46 — multi-mode expansion
• feat: multi-talkgroup channels (denormalise one channel into repeater × talkgroup pairs on export) #36 — multi-talkgroup expansion