Player identity vs game progression: decouple universal Trainer profile from adapter-specific history #178

Child of #174. Closely related to #175 (dynamic tabs) and #176 (Pokémon package extraction).

The hidden Pokémon assumption

Today the primary Trainer tab bundles:

• universal TrainerOS person (local profile/name/emblem, profile editing, ownership and personal preferences);
• Pokémon-specific persona (favorite Pokémon, game trainer context);
• game-specific progress (badges, Journey milestones, Champion Hall);
• cross-game/external integrations (RetroAchievements and actual play history).

This makes a selected Diablo or racing title implicitly show Pokémon progression even though the shell should follow its own game's adapter.

Separate the ownership domains

Host always owns:

• current local Player/Trainer identity, PIN, account links, settings, safe switching and per-user store;
• actual launch/play session history, game registration, media, notification/activity provenance;
• verified RetroAchievements account/provider. Whether a given game has a compatible achievement set is capability-driven.
• one consistent way to view/edit user identity even if no game integration is installed.

Game experience owns:

• names, widgets/faces and progress policies for its second contextual primary slot (e.g. Pokémon Trainer/Journey/Hall, Diablo Chronicle, racing Career);
• Pokémon badges, real Champion snapshots, quest completion, stage/race records, RPG character fields, game-only favorites and milestones only when sourced from verified adapter data;
• context-specific filtering/metadata and optional in-game/Select actions without shell title checks.

A generic Playtime/History view can be shared by any game; it must not be interpreted as evidence of finishing the game. RA achievements remain externally sourced and must not be invented to substitute milestones or embedded in Pokémon-specific logic.

UX decision to finalize in implementation

The label Trainer is not permanent for slot B; it may become Chronicle, Career, Records or another meaningful adapter name. Do not rename the entire user's OS identity or Fluxer profile whenever they select a game.

Ensure universal profile editing, account access and switching remain consistently reachable — as a shared face where appropriate and/or a stable global settings/profile route. Reconcile with Start's existing Switch Trainer and the universal Options (#168) without duplicating power/system controls or trapping a profile behind an incompatible game package. No requirement to keep an oversized permanent Profile panel in every deep game experience.

Acceptance

• Changing selected Adventure does not change or corrupt the current real local user/profile/account identity.
• Pokémon still has true badges/Champion/progression for exact supported saves.
• Generic game or non-Pokémon experience never displays Pokémon-specific favorites, badges or Champion Hall.
• General play history and verified RA remain discoverable when meaningful, without pretending to be game progress.
• Profile creation/edit/PIN/switch/restore works regardless of adapter installation, game selection, or runtime minimized state.
• Navigation by semantic IDs and legacy Trainer/Journey/Hall/RA checkpoint migration preserve same account and history; no cross-user data leaks.
• Help/onboarding, context Select and visual labels consistently distinguish the person/profile from per-game character/progression.

Related: #12, #24, #25, #47, #48, #49, #89, #90, #111, #167–#169, #174–#176.