feat: Implement Phase 5 Quest System (100% complete)

Add YAML-driven quest system with context-aware offering:

Core Implementation:
- Quest data models (Quest, QuestObjective, QuestReward, QuestTriggers)
- QuestService for YAML loading and caching
- QuestEligibilityService with level, location, and probability filtering
- LoreService stub (MockLoreService) ready for Phase 6 Weaviate integration

Quest Content:
- 5 example quests across difficulty tiers (2 easy, 2 medium, 1 hard)
- Quest-centric design: quests define their NPC givers
- Location-based probability weights for natural quest offering

AI Integration:
- Quest offering section in npc_dialogue.j2 template
- Response parser extracts [QUEST_OFFER:quest_id] markers
- AI naturally weaves quest offers into NPC conversations

API Endpoints:
- POST /api/v1/quests/accept - Accept quest offer
- POST /api/v1/quests/decline - Decline quest offer
- POST /api/v1/quests/progress - Update objective progress
- POST /api/v1/quests/complete - Complete quest, claim rewards
- POST /api/v1/quests/abandon - Abandon active quest
- GET /api/v1/characters/{id}/quests - List character quests
- GET /api/v1/quests/{quest_id} - Get quest details

Frontend:
- Quest tracker sidebar with HTMX integration
- Quest offer modal for accept/decline flow
- Quest detail modal for viewing progress
- Combat service integration for kill objective tracking

Testing:
- Unit tests for Quest models and serialization
- Integration tests for full quest lifecycle
- Comprehensive test coverage for eligibility service

Documentation:
- Reorganized docs into /docs/phases/ structure
- Added Phase 5-12 planning documents
- Updated ROADMAP.md with new structure

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

api/app/data/quests/medium/bandit_threat.yaml

@@ -0,0 +1,121 @@
+# Bandit Threat - Combat-focused medium quest
+quest_id: quest_bandit_threat
+name: "The Bandit Threat"
+description: |
+  A gang of bandits has been terrorizing travelers on the roads
+  near Crossville. Mayor Aldric is offering a substantial reward
+  for anyone who can deal with the threat permanently.
+difficulty: medium
+
+# NPC Quest Givers
+quest_giver_npc_ids:
+  - npc_mayor_aldric
+quest_giver_name: "Mayor Aldric Thornwood"
+
+# Location context
+location_id: crossville_village
+region_id: crossville
+
+# Offering conditions
+offering_triggers:
+  location_types: ["town", "official"]
+  specific_locations: ["crossville_village", "crossville_town_hall"]
+  min_character_level: 3
+  max_character_level: 8
+  required_quests_completed: []
+  probability_weights:
+    town: 0.20
+    official: 0.40
+
+# NPC-specific offer dialogue
+npc_offer_dialogues:
+  npc_mayor_aldric:
+    dialogue: |
+      *straightens his chain of office* Crossville faces a grave threat.
+      Bandits have been attacking merchants on the eastern road. Trade
+      is suffering, and I fear for our people's safety. The village
+      will pay handsomely for someone who can... resolve this situation.
+    conditions:
+      min_relationship: 35
+      required_flags: []
+      forbidden_flags: ["failed_bandit_quest"]
+
+# What NPCs know
+npc_quest_knowledge:
+  npc_mayor_aldric:
+    - "The bandits have a camp somewhere in the eastern forest"
+    - "They're led by a man called 'Blackhand' - a former soldier"
+    - "At least a dozen bandits, well-armed and organized"
+    - "Three merchant caravans have been hit in the past month"
+    - "The militia is too small to mount an assault"
+
+# Embedded lore
+lore_context:
+  backstory: |
+    The bandit leader Blackhand was once a soldier in the King's
+    army. After the war ended, he turned to brigandry rather than
+    return to a life of farming. His military training makes his
+    gang far more dangerous than common thieves.
+  world_connections:
+    - "Many veterans turned to banditry after the war - a kingdom-wide problem"
+    - "The mayor may know more about Blackhand than he lets on"
+  regional_hints:
+    - "The eastern forest road is the main trade route to the capital"
+    - "Without trade, Crossville's economy will suffer greatly"
+
+# Narrative hooks
+dialogue_templates:
+  narrative_hooks:
+    - "speaks of the economic impact on the village"
+    - "mentions concerned merchants refusing to travel"
+    - "hints at political pressure from higher authorities"
+    - "shows genuine worry for the common folk"
+  ambient_hints:
+    - "You notice fewer merchants in the market than expected"
+    - "Guards at the village gate look nervous and understaffed"
+    - "Wanted posters for 'Blackhand' are posted on walls"
+
+# Objectives
+objectives:
+  - objective_id: find_camp
+    description: "Locate the bandit camp in the eastern forest"
+    objective_type: discover
+    required_progress: 1
+    target_location_id: bandit_camp
+
+  - objective_id: defeat_bandits
+    description: "Defeat the bandits"
+    objective_type: kill
+    required_progress: 8
+    target_enemy_type: bandit
+
+  - objective_id: defeat_blackhand
+    description: "Defeat or capture Blackhand"
+    objective_type: kill
+    required_progress: 1
+    target_enemy_type: blackhand_leader
+
+# Rewards
+rewards:
+  gold: 200
+  experience: 350
+  items:
+    - blackhand_sword
+  relationship_bonuses:
+    npc_mayor_aldric: 20
+  unlocks_quests: ["quest_mayors_secret"]
+  reveals_locations: ["bandit_camp"]
+
+# Completion dialogue
+completion_dialogue:
+  npc_mayor_aldric: |
+    *visible relief* The bandits are dealt with? This is excellent
+    news. You've done Crossville a great service. *hands over a
+    heavy coin purse* Your reward, as promised. And... I may have
+    other matters that require someone of your capabilities. We
+    should speak again soon.
+
+tags:
+  - combat
+  - exploration
+  - story