refactor(plugins/platforms): migrate IRC + Teams to new env_enablement + cron_deliver hooks

Adopt the generic platform-plugin hooks landed in the preceding commit
so IRC and Teams get env-only config detection and cron home-channel
delivery without living in cron/scheduler.py's hardcoded sets.

IRC (plugins/platforms/irc/):
- adapter.py: new _env_enablement() seeds server, channel, port,
  nickname, use_tls, server_password, nickserv_password, and a
  home_channel dict into PlatformConfig on env-only setups.
  IRC_HOME_CHANNEL defaults to IRC_CHANNEL so deliver=irc cron jobs
  route to the joined channel by default.
- adapter.py: register_platform() gains env_enablement_fn=_env_enablement
  and cron_deliver_env_var='IRC_HOME_CHANNEL'.
- plugin.yaml: rich requires_env / optional_env with description,
  prompt, password, url for every IRC env var.  Hardcoded IRC entries
  in hermes_cli/config.py still win (back-compat), but the plugin now
  carries its own metadata.

Teams (plugins/platforms/teams/):
- adapter.py: new _env_enablement() seeds client_id, client_secret,
  tenant_id, port, and home_channel into PlatformConfig.  Closes the
  long-standing gap where TEAMS_HOME_CHANNEL was documented but never
  wired up.
- adapter.py: register_platform() gains env_enablement_fn=_env_enablement
  and cron_deliver_env_var='TEAMS_HOME_CHANNEL' — deliver=teams cron
  jobs now work.
- plugin.yaml: rich requires_env / optional_env with description,
  prompt, password, url for every Teams env var.  Surfaces them in
  'hermes config' UI for the first time (Teams had no OPTIONAL_ENV_VARS
  entries before this).

Zero behavior change for existing users: env_enablement_fn is only
called when env vars are set, and the registry's config-first-env-fallback
path in validate_config / is_connected is unchanged.

plugins/platforms/teams/adapter.py

@@ -152,6 +152,42 @@ def is_connected(config) -> bool:
     return validate_config(config)
 
 
+def _env_enablement() -> dict | None:
+    """Seed ``PlatformConfig.extra`` from env vars during gateway config load.
+
+    Called by the platform registry's env-enablement hook BEFORE adapter
+    construction, so ``gateway status`` and ``get_connected_platforms()``
+    reflect env-only configuration without instantiating the Teams SDK.
+    Returns ``None`` when Teams isn't minimally configured.
+
+    The special ``home_channel`` key in the returned dict becomes a proper
+    ``HomeChannel`` dataclass on the ``PlatformConfig`` via the core hook.
+    """
+    client_id = os.getenv("TEAMS_CLIENT_ID", "").strip()
+    client_secret = os.getenv("TEAMS_CLIENT_SECRET", "").strip()
+    tenant_id = os.getenv("TEAMS_TENANT_ID", "").strip()
+    if not (client_id and client_secret and tenant_id):
+        return None
+    seed: dict = {
+        "client_id": client_id,
+        "client_secret": client_secret,
+        "tenant_id": tenant_id,
+    }
+    port = os.getenv("TEAMS_PORT", "").strip()
+    if port:
+        try:
+            seed["port"] = int(port)
+        except ValueError:
+            pass
+    home = os.getenv("TEAMS_HOME_CHANNEL", "").strip()
+    if home:
+        seed["home_channel"] = {
+            "chat_id": home,
+            "name": os.getenv("TEAMS_HOME_CHANNEL_NAME", "Home"),
+        }
+    return seed
+
+
 # Keep the old name as an alias so existing test imports don't break.
 check_teams_requirements = check_requirements
 
@@ -702,6 +738,14 @@ def register(ctx) -> None:
         required_env=["TEAMS_CLIENT_ID", "TEAMS_CLIENT_SECRET", "TEAMS_TENANT_ID"],
         install_hint="pip install microsoft-teams-apps aiohttp",
         setup_fn=interactive_setup,
+        # Env-driven auto-configuration — seeds PlatformConfig.extra with
+        # client_id/secret/tenant + port + home_channel so env-only setups
+        # show up in gateway status without instantiating the Teams SDK.
+        env_enablement_fn=_env_enablement,
+        # Cron home-channel delivery support.  Lets deliver=teams cron
+        # jobs route to the configured Teams chat/channel without editing
+        # cron/scheduler.py's hardcoded sets.
+        cron_deliver_env_var="TEAMS_HOME_CHANNEL",
         # Auth env vars for _is_user_authorized() integration
         allowed_users_env="TEAMS_ALLOWED_USERS",
         allow_all_env="TEAMS_ALLOW_ALL_USERS",