Modularize bot: per-guild config system for roles/channels/categories

- Add utils/guild_config.py: centralized config loader per guild (data/guilds/{id}.json)
- Add commandes/config.py: /config set_role, /config set_channel, /config set_category, /config voir, /config reset
- Replace ALL hardcoded role IDs (banquier, gouvernement, citoyen, staff, ems, permis, fbm, ursaff, etc.) with guild_config lookups
- Replace ALL hardcoded channel IDs (welcome, candidature, questions, mp_reception) with guild_config lookups
- Replace ALL hardcoded category IDs (ticket) with guild_config lookups
- Remove duplicate commandes/welcome_message.py (kept utils/ version)
- Remove 20+ hardcoded snowflake IDs across 22 files
- Guilds configure via /config on Discord, no code changes needed

commandes/annonces_sessions.py

@@ -3,9 +3,7 @@ from discord import app_commands
 from discord.ext import commands, tasks
 import dateparser
 from datetime import datetime, timezone
-
-ROLE_PING_ID = 1278319901651632138 # ID du rôle citoyen      # Rôle pour l'annonce principale
-REMINDER_ROLE_ID = 1303750986900439151 # ID du rôle rappels sessions   # Rôle pour les rappels (à adapter !)
+from utils.guild_config import get_role_id
 
 presence_data = {}
 
@@ -114,6 +112,9 @@ class AnnonceSession(commands.Cog):
         reminder1_date = reminder1_date.astimezone(timezone.utc)
         reminder2_date = reminder2_date.astimezone(timezone.utc)
 
+        ping_role_id = get_role_id(interaction.guild.id, "citoyen")
+        reminder_role_id = get_role_id(interaction.guild.id, "session_reminders")
+
         message = (
             "# <:VV:1339237574593609780>  - **SESSION VICTORIA’S VICE**\n"
             "\n"
@@ -130,7 +131,7 @@ class AnnonceSession(commands.Cog):
             "> - Je serai absent : <:uncheck:1297296882778902598> **(0)**\n"
             "> - Je serai en retard : ⏰ **(0)**\n"
             "---"
-            f">  - **`PING`** : <@&{ROLE_PING_ID}>"
+            f">  - **`PING`** : <@&{ping_role_id}>"
         )
 
         await interaction.response.send_message(
@@ -208,8 +209,9 @@ class AnnonceSession(commands.Cog):
         channel = self.bot.get_channel(data["channel_id"])
         if channel:
             msg = await channel.fetch_message(msg_id)
+            reminder_role_id = get_role_id(data.get("guild_id", 0), "session_reminders")
             await channel.send(
-                f"<@&{REMINDER_ROLE_ID}> ⏰ **{label}**\nLa session RP approche !\nAnnonce : {msg.jump_url}"
+                f"<@&{reminder_role_id}> ⏰ **{label}**\nLa session RP approche !\nAnnonce : {msg.jump_url}"
             )
 
     @check_sessions.before_loop