fix(cli): respect HERMES_HOME in all remaining hardcoded ~/.hermes paths

Several files resolved paths via Path.home() / ".hermes" or
os.path.expanduser("~/.hermes/..."), bypassing the HERMES_HOME
environment variable. This broke isolation when running multiple
Hermes instances with distinct HERMES_HOME directories.

Replace all hardcoded paths with calls to get_hermes_home() from
hermes_cli.config, consistent with the rest of the codebase.

Files fixed:
- tools/process_registry.py (processes.json)
- gateway/pairing.py (pairing/)
- gateway/sticker_cache.py (sticker_cache.json)
- gateway/channel_directory.py (channel_directory.json, sessions.json)
- gateway/config.py (gateway.json, config.yaml, sessions_dir)
- gateway/mirror.py (sessions/)
- gateway/hooks.py (hooks/)
- gateway/platforms/base.py (image_cache/, audio_cache/, document_cache/)
- gateway/platforms/whatsapp.py (whatsapp/session)
- gateway/delivery.py (cron/output)
- agent/auxiliary_client.py (auth.json)
- agent/prompt_builder.py (SOUL.md)
- cli.py (config.yaml, images/, pastes/, history)
- run_agent.py (logs/)
- tools/environments/base.py (sandboxes/)
- tools/environments/modal.py (modal_snapshots.json)
- tools/environments/singularity.py (singularity_snapshots.json)
- tools/tts_tool.py (audio_cache)
- hermes_cli/status.py (cron/jobs.json, sessions.json)
- hermes_cli/gateway.py (logs/, whatsapp session)
- hermes_cli/main.py (whatsapp/session)

Tests updated to use HERMES_HOME env var instead of patching Path.home().

Closes #892

(cherry picked from commit 78ac1bba43b8b74a934c6172f2c29bb4d03164b9)

hermes_cli/gateway.py

@@ -13,7 +13,7 @@ from pathlib import Path
 
 PROJECT_ROOT = Path(__file__).parent.parent.resolve()
 
-from hermes_cli.config import get_env_value, save_env_value
+from hermes_cli.config import get_env_value, get_hermes_home, save_env_value
 from hermes_cli.setup import (
     print_header, print_info, print_success, print_warning, print_error,
     prompt, prompt_choice, prompt_yes_no,
@@ -283,7 +283,7 @@ def systemd_status(deep: bool = False):
 def generate_launchd_plist() -> str:
     python_path = get_python_path()
     working_dir = str(PROJECT_ROOT)
-    log_dir = Path.home() / ".hermes" / "logs"
+    log_dir = get_hermes_home() / "logs"
     log_dir.mkdir(parents=True, exist_ok=True)
     
     return f"""<?xml version="1.0" encoding="UTF-8"?>
@@ -380,7 +380,7 @@ def launchd_status(deep: bool = False):
         print("✗ Gateway service is not loaded")
     
     if deep:
-        log_file = Path.home() / ".hermes" / "logs" / "gateway.log"
+        log_file = get_hermes_home() / "logs" / "gateway.log"
         if log_file.exists():
             print()
             print("Recent logs:")
@@ -557,7 +557,7 @@ def _platform_status(platform: dict) -> str:
     val = get_env_value(token_var)
     if token_var == "WHATSAPP_ENABLED":
         if val and val.lower() == "true":
-            session_file = Path.home() / ".hermes" / "whatsapp" / "session" / "creds.json"
+            session_file = get_hermes_home() / "whatsapp" / "session" / "creds.json"
             if session_file.exists():
                 return "configured + paired"
             return "enabled, not paired"