docs: organize diagrams to mirror code layout (util/ + features/)

Move flat docs/diagrams/*.puml into a hierarchy matching the source
package structure:

  docs/diagrams/
  ├── bootstrap-sequence.puml         (cross-cutting)
  ├── events-diagram.puml             (cross-feature)
  ├── util/
  │   ├── command-class-diagram.puml
  │   ├── database-diagram.puml
  │   ├── messages-class-diagram.puml
  │   ├── broadcasts-class-diagram.puml
  │   └── gui-class-diagram.puml
  └── features/
      ├── team/
      │   ├── team-class-diagram.puml
      │   ├── team-config-class-diagram.puml
      │   ├── builtin-commands-diagram.puml
      │   ├── team-create-sequence.puml
      │   ├── team-create-activity.puml
      │   └── team-join-sequence.puml
      ├── player/
      │   └── player-class-diagram.puml
      └── moderation/
          └── moderation-class-diagram.puml

README.md diagram index split into 4 sections (overview, util,
features/team, features/player, features/moderation) for readability;
all links updated. features.md auto-updated by sed for the new paths.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

docs/diagrams/util/broadcasts-class-diagram.puml

@@ -0,0 +1,102 @@
+@startuml broadcasts-class-diagram
+title CR-Core — Broadcast service (class diagram)
+
+skinparam classAttributeIconSize 0
+hide empty members
+
+package "fr.luc.crcore.util.broadcast" {
+
+  enum BroadcastAudience {
+    NONE
+    LEADER
+    TEAM
+    ADMIN
+    ALL
+  }
+
+  class BroadcastContext {
+    - team: Team
+    - involvedPlayerId: UUID
+    - placeholders: Map<String, String>
+    --
+    + {static} of(team): BroadcastContext
+    + {static} empty(): BroadcastContext
+    + involving(playerId): BroadcastContext
+    + with(key, value): BroadcastContext
+    + getTeam(): Optional<Team>
+    + getInvolvedPlayerId(): Optional<UUID>
+    + getPlaceholders(): Map<String, String>
+    + toPlaceholderPairs(): Object[]
+  }
+
+  interface BroadcastService {
+    + broadcast(eventKey, context): void
+    + getAudiences(eventKey): List<BroadcastAudience>
+    + reload(): void
+  }
+
+  class CRCoreBroadcastListener {
+    - broadcasts: BroadcastService
+    + registerOn(plugin: JavaPlugin): void
+    --
+    @ onTeamCreate(TeamCreateEvent)
+    @ onTeamDissolve(TeamDissolveEvent)
+    @ onTeamMemberAdd(TeamMemberAddEvent)
+    @ onTeamMemberRemove(TeamMemberRemoveEvent)
+    @ onPlayerJoinTeam(PlayerJoinTeamEvent)
+    @ onLeadershipTransfer(TeamLeadershipTransferEvent)
+    @ onVisibilityChange(TeamVisibilityChangeEvent)
+    @ onTeamScoreChange(TeamScoreChangeEvent)
+    @ onTeamSpawnChange(TeamSpawnPointChangeEvent)
+    @ onProfileCreate(PlayerProfileCreateEvent)
+    @ onProfileDelete(PlayerProfileDeleteEvent)
+    @ onPlayerScoreChange(PlayerScoreChangeEvent)
+  }
+  CRCoreBroadcastListener ..|> "org.bukkit.event.Listener"
+
+  package "fr.luc.crcore.util.broadcast.impl" {
+    class YamlBroadcastService {
+      - plugin: JavaPlugin
+      - messages: MessagesService
+      - defaults: Map<String, List<BroadcastAudience>>
+      - audiences: Map<String, List<BroadcastAudience>>
+      - userFile: File
+      --
+      + YamlBroadcastService(plugin, messages)
+      - loadDefaultsFromResource(): void
+      - ensureUserFile(): void
+      - rebuildEffectiveAudiences(): void
+      - resolveRecipients(list, ctx): Set<Player>
+    }
+    YamlBroadcastService ..|> BroadcastService
+  }
+
+  BroadcastService ..> BroadcastContext : consumes
+  BroadcastContext --> BroadcastAudience
+  YamlBroadcastService --> "fr.luc.crcore.util.message.MessagesService" : reads templates
+  CRCoreBroadcastListener --> BroadcastService : delegates
+  CRCoreBroadcastListener ..> BroadcastContext : builds
+}
+
+package "fr.luc.crcore" {
+  class CRCore {
+    + broadcasts(): BroadcastService
+    # buildBroadcastService(messages): BroadcastService
+  }
+  CRCore "1" *-- "1" BroadcastService : owns
+  CRCore ..> CRCoreBroadcastListener : registers
+}
+
+note bottom of YamlBroadcastService
+  Modèle "un seul fichier par plugin" :
+
+  Sources en mémoire :
+    1. crcore-broadcasts.yml         ← jar (fallback)
+    2. <plugin>-broadcasts.yml       ← dataFolder (édité par l'admin)
+
+  Séparation routes / templates :
+    - Routes = ce fichier (qui reçoit quoi)
+    - Templates = MessagesService (clés <event>.broadcast)
+end note
+
+@enduml