feat: register Mattermost and Matrix env vars in OPTIONAL_ENV_VARS

Adds both platforms to the config system so hermes setup, hermes doctor,
and hermes config properly discover and manage their env vars.

- MATTERMOST_URL, MATTERMOST_TOKEN, MATTERMOST_ALLOWED_USERS
- MATRIX_HOMESERVER, MATRIX_ACCESS_TOKEN, MATRIX_USER_ID, MATRIX_ALLOWED_USERS
- Extra env keys for .env sanitizer: MATTERMOST_HOME_CHANNEL,
  MATTERMOST_REPLY_MODE, MATRIX_PASSWORD, MATRIX_ENCRYPTION, MATRIX_HOME_ROOM

hermes_cli/config.py

@@ -37,6 +37,8 @@ _EXTRA_ENV_KEYS = frozenset({
     "DINGTALK_CLIENT_ID", "DINGTALK_CLIENT_SECRET",
     "TERMINAL_ENV", "TERMINAL_SSH_KEY", "TERMINAL_SSH_PORT",
     "WHATSAPP_MODE", "WHATSAPP_ENABLED",
+    "MATTERMOST_HOME_CHANNEL", "MATTERMOST_REPLY_MODE",
+    "MATRIX_PASSWORD", "MATRIX_ENCRYPTION", "MATRIX_HOME_ROOM",
 })
 
 import yaml
@@ -692,6 +694,55 @@ OPTIONAL_ENV_VARS = {
         "password": True,
         "category": "messaging",
     },
+    "MATTERMOST_URL": {
+        "description": "Mattermost server URL (e.g. https://mm.example.com)",
+        "prompt": "Mattermost server URL",
+        "url": "https://mattermost.com/deploy/",
+        "password": False,
+        "category": "messaging",
+    },
+    "MATTERMOST_TOKEN": {
+        "description": "Mattermost bot token or personal access token",
+        "prompt": "Mattermost bot token",
+        "url": None,
+        "password": True,
+        "category": "messaging",
+    },
+    "MATTERMOST_ALLOWED_USERS": {
+        "description": "Comma-separated Mattermost user IDs allowed to use the bot",
+        "prompt": "Allowed Mattermost user IDs (comma-separated)",
+        "url": None,
+        "password": False,
+        "category": "messaging",
+    },
+    "MATRIX_HOMESERVER": {
+        "description": "Matrix homeserver URL (e.g. https://matrix.example.org)",
+        "prompt": "Matrix homeserver URL",
+        "url": "https://matrix.org/ecosystem/servers/",
+        "password": False,
+        "category": "messaging",
+    },
+    "MATRIX_ACCESS_TOKEN": {
+        "description": "Matrix access token (preferred over password login)",
+        "prompt": "Matrix access token",
+        "url": None,
+        "password": True,
+        "category": "messaging",
+    },
+    "MATRIX_USER_ID": {
+        "description": "Matrix user ID (e.g. @hermes:example.org)",
+        "prompt": "Matrix user ID (@user:server)",
+        "url": None,
+        "password": False,
+        "category": "messaging",
+    },
+    "MATRIX_ALLOWED_USERS": {
+        "description": "Comma-separated Matrix user IDs allowed to use the bot (@user:server format)",
+        "prompt": "Allowed Matrix user IDs (comma-separated)",
+        "url": None,
+        "password": False,
+        "category": "messaging",
+    },
     "GATEWAY_ALLOW_ALL_USERS": {
         "description": "Allow all users to interact with messaging bots (true/false). Default: false.",
         "prompt": "Allow all users (true/false)",