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)

tests/gateway/test_channel_directory.py

@@ -1,6 +1,7 @@
 """Tests for gateway/channel_directory.py — channel resolution and display."""
 
 import json
+import os
 from pathlib import Path
 from unittest.mock import patch
 
@@ -122,7 +123,7 @@ class TestResolveChannelName:
 class TestBuildFromSessions:
     def _write_sessions(self, tmp_path, sessions_data):
         """Write sessions.json at the path _build_from_sessions expects."""
-        sessions_path = tmp_path / ".hermes" / "sessions" / "sessions.json"
+        sessions_path = tmp_path / "sessions" / "sessions.json"
         sessions_path.parent.mkdir(parents=True)
         sessions_path.write_text(json.dumps(sessions_data))
 
@@ -152,7 +153,7 @@ class TestBuildFromSessions:
             },
         })
 
-        with patch.object(Path, "home", return_value=tmp_path):
+        with patch.dict(os.environ, {"HERMES_HOME": str(tmp_path)}):
             entries = _build_from_sessions("telegram")
 
         assert len(entries) == 2
@@ -161,7 +162,7 @@ class TestBuildFromSessions:
         assert "Bob" in names
 
     def test_missing_sessions_file(self, tmp_path):
-        with patch.object(Path, "home", return_value=tmp_path):
+        with patch.dict(os.environ, {"HERMES_HOME": str(tmp_path)}):
             entries = _build_from_sessions("telegram")
         assert entries == []
 
@@ -171,7 +172,7 @@ class TestBuildFromSessions:
             "s2": {"origin": {"platform": "telegram", "chat_id": "123", "chat_name": "X"}},
         })
 
-        with patch.object(Path, "home", return_value=tmp_path):
+        with patch.dict(os.environ, {"HERMES_HOME": str(tmp_path)}):
             entries = _build_from_sessions("telegram")
 
         assert len(entries) == 1

tests/tools/test_clipboard.py

@@ -808,7 +808,7 @@ class TestTryAttachClipboardImage:
         with patch("hermes_cli.clipboard.save_clipboard_image", return_value=True):
             cli._try_attach_clipboard_image()
         path = cli._attached_images[0]
-        assert path.parent == Path.home() / ".hermes" / "images"
+        assert path.parent == Path(os.environ["HERMES_HOME"]) / "images"
         assert path.name.startswith("clip_")
         assert path.suffix == ".png"