fix: make display_hermes_home imports lazy to prevent ImportError during hermes update (#3776)

When a user runs 'hermes update', the Python process caches old modules
in sys.modules.  After git pull updates files on disk, lazy imports of
newly-updated modules fail because they try to import display_hermes_home
from the cached (old) hermes_constants which doesn't have the function.

This specifically broke the gateway auto-restart in cmd_update — importing
hermes_cli/gateway.py triggered the top-level 'from hermes_constants
import display_hermes_home' against the cached old module.  The ImportError
was silently caught, so the gateway was never restarted after update.

Users with a running gateway then hit the ImportError on their next
Telegram/Discord message when the stale gateway process lazily loaded
run_agent.py (new version) which also had the top-level import.

Fixes:
- hermes_cli/gateway.py: lazy import at call site (line 940)
- run_agent.py: lazy import at call site (line 6927)
- tools/terminal_tool.py: lazy imports at 3 call sites
- tools/tts_tool.py: static schema string (no module-level call)
- hermes_cli/auth.py: lazy import at call site (line 2024)
- hermes_cli/main.py: reload hermes_constants after git pull in cmd_update

Also fixes 4 pre-existing test failures in test_parse_env_var caused by
NameError on display_hermes_home in terminal_tool.py.

hermes_cli/setup.py

@@ -289,7 +289,7 @@ from hermes_cli.config import (
     get_env_value,
     ensure_hermes_home,
 )
-from hermes_constants import display_hermes_home
+# display_hermes_home imported lazily at call sites (stale-module safety during hermes update)
 
 from hermes_cli.colors import Colors, color
 
@@ -684,7 +684,8 @@ def _print_setup_summary(config: dict, hermes_home):
         print_warning(
             "Some tools are disabled. Run 'hermes setup tools' to configure them,"
         )
-        print_warning(f"or edit {display_hermes_home()}/.env directly to add the missing API keys.")
+        from hermes_constants import display_hermes_home as _dhh
+        print_warning(f"or edit {_dhh()}/.env directly to add the missing API keys.")
         print()
 
     # Done banner
@@ -707,7 +708,8 @@ def _print_setup_summary(config: dict, hermes_home):
     print()
 
     # Show file locations prominently
-    print(color(f"📁 All your files are in {display_hermes_home()}/:", Colors.CYAN, Colors.BOLD))
+    from hermes_constants import display_hermes_home as _dhh
+    print(color(f"📁 All your files are in {_dhh()}/:", Colors.CYAN, Colors.BOLD))
     print()
     print(f"   {color('Settings:', Colors.YELLOW)}  {get_config_path()}")
     print(f"   {color('API Keys:', Colors.YELLOW)}  {get_env_path()}")
@@ -2838,7 +2840,8 @@ def setup_gateway(config: dict):
         save_env_value("WEBHOOK_ENABLED", "true")
         print()
         print_success("Webhooks enabled! Next steps:")
-        print_info(f"   1. Define webhook routes in {display_hermes_home()}/config.yaml")
+        from hermes_constants import display_hermes_home as _dhh
+        print_info(f"   1. Define webhook routes in {_dhh()}/config.yaml")
         print_info("   2. Point your service (GitHub, GitLab, etc.) at:")
         print_info("      http://your-server:8644/webhooks/<route-name>")
         print()