feat: Track class evolution history for lore display

[madjin]

Summary

Record class transitions for rich profile lore (e.g., "Once a Scribe, now a Maintainer").

Database Schema

CREATE TABLE user_class_history (
  id TEXT PRIMARY KEY,
  username TEXT NOT NULL REFERENCES users(username),
  from_class TEXT NOT NULL,
  to_class TEXT NOT NULL,
  transition_date TEXT NOT NULL,
  reason TEXT -- "evolution", "respec", "tier_up"
);

Profile Display

{
  "classHistory": [
    { "class": "Contributor", "date": "2024-10-15", "reason": "joined" },
    { "class": "Scribe", "date": "2024-11-01", "reason": "evolution" },
    { "class": "Archivist", "date": "2025-01-01", "reason": "evolution" }
  ],
  "lore": "Once a Contributor, evolved through the Scribe Order to become an Archivist"
}

Acceptance Criteria

• Database table for class history
• Record transitions on class change
• Generate lore text from history
• Display lore on profile page

Related

• Depends on feat: Implement full Orders & Evolution class tree #194 (Orders & Evolution system)