feat(examples): expand baker-family with relationships and world context

Added comprehensive v0.3.0 feature demonstration:

Characters (5 total):
- Martha & Jane (married lesbian couple, co-owners of bakery)
- Emma (their daughter, apprentice baker)
- Henry (loyal customer, retired teacher)
- Roland (competing baker)

New declarations:
- 6 relationships with asymmetric perspectives (Marriage, ParentChild×2,
  BusinessPartnership, CustomerRelationship, Competition)
- Locations with prose (MarthasBakery, MainStreet)
- Institution (BakersGuild)
- Life arcs (MarriageQuality, BusinessGrowth)

Features demonstrated:
- Concept comparison usage (skill_tier: Master/Journeyman)
- Life arc applied to relationship
- Asymmetric participant perspectives
- Family coherence across files

examples/baker-family/characters/jane.sb

@@ -15,6 +15,7 @@ character Jane from Baker {
     specialty: "pastries"
     baking_skill: 0.85
     customer_relations: 0.80
+    skill_tier: Journeyman
 
     // General traits
     energy: 0.75
@@ -26,13 +27,13 @@ character Jane from Baker {
 
     ---backstory
     Jane trained at a culinary school in the capital before returning
-    to his hometown and meeting Martha. His specialty is delicate
+    to her hometown and meeting Martha. Her specialty is delicate
     pastries and elaborate wedding cakes. While Martha handles the
     bread and business, Jane focuses on the artistic creations that
     draw customers from neighboring towns.
 
-    He's more of a night owl by nature, but has adapted to the baker's
-    early schedule over the years. His croissants are legendary.
+    She is more of a night owl by nature, but has adapted to the baker's
+    early schedule over the years. Her croissants are legendary.
     ---
 }