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)

gateway/platforms/base.py

@@ -25,6 +25,7 @@ sys.path.insert(0, str(_Path(__file__).resolve().parents[2]))
 
 from gateway.config import Platform, PlatformConfig
 from gateway.session import SessionSource, build_session_key
+from hermes_cli.config import get_hermes_home
 
 
 GATEWAY_SECRET_CAPTURE_UNSUPPORTED_MESSAGE = (
@@ -42,8 +43,8 @@ GATEWAY_SECRET_CAPTURE_UNSUPPORTED_MESSAGE = (
 # (e.g. Telegram file URLs expire after ~1 hour).
 # ---------------------------------------------------------------------------
 
-# Default location: ~/.hermes/image_cache/
-IMAGE_CACHE_DIR = Path(os.path.expanduser("~/.hermes/image_cache"))
+# Default location: {HERMES_HOME}/image_cache/
+IMAGE_CACHE_DIR = get_hermes_home() / "image_cache"
 
 
 def get_image_cache_dir() -> Path:
@@ -125,7 +126,7 @@ def cleanup_image_cache(max_age_hours: int = 24) -> int:
 # here so the STT tool (OpenAI Whisper) can transcribe them from local files.
 # ---------------------------------------------------------------------------
 
-AUDIO_CACHE_DIR = Path(os.path.expanduser("~/.hermes/audio_cache"))
+AUDIO_CACHE_DIR = get_hermes_home() / "audio_cache"
 
 
 def get_audio_cache_dir() -> Path:
@@ -184,7 +185,7 @@ async def cache_audio_from_url(url: str, ext: str = ".ogg") -> str:
 # here so the agent can reference them by local file path.
 # ---------------------------------------------------------------------------
 
-DOCUMENT_CACHE_DIR = Path(os.path.expanduser("~/.hermes/document_cache"))
+DOCUMENT_CACHE_DIR = get_hermes_home() / "document_cache"
 
 SUPPORTED_DOCUMENT_TYPES = {
     ".pdf": "application/pdf",

gateway/platforms/whatsapp.py

@@ -26,6 +26,8 @@ _IS_WINDOWS = platform.system() == "Windows"
 from pathlib import Path
 from typing import Dict, List, Optional, Any
 
+from hermes_cli.config import get_hermes_home
+
 logger = logging.getLogger(__name__)
 
 
@@ -132,7 +134,7 @@ class WhatsAppAdapter(BasePlatformAdapter):
         )
         self._session_path: Path = Path(config.extra.get(
             "session_path",
-            Path.home() / ".hermes" / "whatsapp" / "session"
+            get_hermes_home() / "whatsapp" / "session"
         ))
         self._message_queue: asyncio.Queue = asyncio.Queue()
         self._bridge_log_fh = None