feat(docs): add detailed features and business flow diagrams

- Introduced new interaction and community features, including comments and private messaging.
- Added technical diagrams for critical workflows: authentication, content publication, and messaging.
- Enhanced data model documentation with support for comments and messaging tables.
- Updated API references with endpoints for comments, messaging, and user search.
- Integrated post-quantum cryptography for improved data protection.

documentation/content/docs/database.mdx

@@ -18,13 +18,24 @@ erDiagram
     USER ||--o{ API_KEY : "genere"
     USER ||--o{ AUDIT_LOG : "genere"
     USER ||--o{ FAVORITE : "ajoute"
+    USER ||--o{ COMMENT : "rédige"
+    USER ||--o{ COMMENT_LIKE : "aime"
+    USER ||--o{ CONVERSATION_PARTICIPANT : "participe"
+    USER ||--o{ MESSAGE : "envoie"
     
     CONTENT ||--o{ CONTENT_TAG : "possede"
     TAG ||--o{ CONTENT_TAG : "est_lie_a"
     CONTENT ||--o{ REPORT : "est_signale"
     CONTENT ||--o{ FAVORITE : "est_mis_en"
+    CONTENT ||--o{ COMMENT : "reçoit"
     TAG ||--o{ REPORT : "est_signale"
 
+    COMMENT ||--o{ COMMENT : "possède des réponses"
+    COMMENT ||--o{ COMMENT_LIKE : "est aimé par"
+
+    CONVERSATION ||--o{ CONVERSATION_PARTICIPANT : "regroupe"
+    CONVERSATION ||--o{ MESSAGE : "contient"
+
     CATEGORY ||--o{ CONTENT : "catégorise"
 
     ROLE ||--o{ USER_ROLE : "attribue_a"
@@ -45,6 +56,15 @@ erDiagram
         string type
         string storage_key
     }
+    COMMENT {
+        string text
+    }
+    CONVERSATION {
+        timestamp created_at
+    }
+    MESSAGE {
+        string text
+    }
     TAG {
         string name
         string slug
@@ -140,6 +160,39 @@ erDiagram
         uuid content_id PK, FK
         uuid tag_id PK, FK
     }
+    comments {
+        uuid id PK
+        uuid content_id FK
+        uuid user_id FK
+        uuid parent_id FK
+        text text
+        timestamp created_at
+        timestamp updated_at
+        timestamp deleted_at
+    }
+    comment_likes {
+        uuid comment_id PK, FK
+        uuid user_id PK, FK
+        timestamp created_at
+    }
+    conversations {
+        uuid id PK
+        timestamp created_at
+        timestamp updated_at
+    }
+    conversation_participants {
+        uuid conversation_id PK, FK
+        uuid user_id PK, FK
+        timestamp joined_at
+    }
+    messages {
+        uuid id PK
+        uuid conversation_id FK
+        uuid sender_id FK
+        text text
+        timestamp created_at
+        timestamp read_at
+    }
     roles {
         uuid id PK
         varchar name
@@ -225,6 +278,15 @@ erDiagram
     users ||--o{ sessions : "user_id"
     users ||--o{ api_keys : "user_id"
     users ||--o{ audit_logs : "user_id"
+    contents ||--o{ comments : "content_id"
+    users ||--o{ comments : "user_id"
+    comments ||--o{ comments : "parent_id"
+    comments ||--o{ comment_likes : "comment_id"
+    users ||--o{ comment_likes : "user_id"
+    conversations ||--o{ conversation_participants : "conversation_id"
+    users ||--o{ conversation_participants : "user_id"
+    conversations ||--o{ messages : "conversation_id"
+    users ||--o{ messages : "sender_id"
 ```
 
 ### Physique (MPD)
@@ -278,6 +340,7 @@ erDiagram
 
 #### Sécurité et Chiffrement
 - **Chiffrement PGP (Native)** : Les colonnes `email` et `two_factor_secret` sont stockées au format `bytea` et chiffrées/déchiffrées via les fonctions `pgp_sym_encrypt` et `pgp_sym_decrypt` de PostgreSQL (via l'extension `pgcrypto`).
+- **Cryptographie Post-Quantique** : Utilisation de la bibliothèque `@noble/post-quantum` pour anticiper les futures menaces cryptographiques.
 - **Hachage aveugle (Blind Indexing)** : La colonne `email_hash` stocke un hash (SHA-256) de l'email pour permettre les recherches d'unicité et les recherches rapides sans déchiffrer la donnée.
 
 #### Index et Optimisations