feat(honcho): context injection overhaul, 5-tool surface, cost safety, session isolation (#10619)

Salvaged from PR #9884 by erosika. Cherry-picked plugin changes onto
current main with minimal core modifications.

Plugin changes (plugins/memory/honcho/):
- New honcho_reasoning tool (5th tool, splits LLM calls from honcho_context)
- Two-layer context injection: base context (summary + representation + card)
  on contextCadence, dialectic supplement on dialecticCadence
- Multi-pass dialectic depth (1-3 passes) with early bail-out on strong signal
- Cold/warm prompt selection based on session state
- dialecticCadence defaults to 3 (was 1) — ~66% fewer Honcho LLM calls
- Session summary injection for conversational continuity
- Bidirectional peer targeting on all 5 tools
- Correctness fixes: peer param fallback, None guard on set_peer_card,
  schema validation, signal_sufficient anchored regex, mid->medium level fix

Core changes (~20 lines across 3 files):
- agent/memory_manager.py: Enhanced sanitize_context() to strip full
  <memory-context> blocks and system notes (prevents leak from saveMessages)
- run_agent.py: gateway_session_key param for stable per-chat Honcho sessions,
  on_turn_start() call before prefetch_all() for cadence tracking,
  sanitize_context() on user messages to strip leaked memory blocks
- gateway/run.py: skip_memory=True on 2 temp agents (prevents orphan sessions),
  gateway_session_key threading to main agent

Tests: 509 passed (3 skipped — honcho SDK not installed locally)
Docs: Updated honcho.md, memory-providers.md, tools-reference.md, SKILL.md

Co-authored-by: erosika <erosika@users.noreply.github.com>

website/docs/reference/tools-reference.md

@@ -72,7 +72,7 @@ In addition to built-in tools, Hermes can load tools dynamically from MCP server
 | `ha_list_services` | List available Home Assistant services (actions) for device control. Shows what actions can be performed on each device type and what parameters they accept. Use this to discover how to control devices found via ha_list_entities. | — |
 
 :::note
-**Honcho tools** (`honcho_conclude`, `honcho_context`, `honcho_profile`, `honcho_search`) are no longer built-in. They are available via the Honcho memory provider plugin at `plugins/memory/honcho/`. See [Plugins](../user-guide/features/plugins.md) for installation and usage.
+**Honcho tools** (`honcho_profile`, `honcho_search`, `honcho_context`, `honcho_reasoning`, `honcho_conclude`) are no longer built-in. They are available via the Honcho memory provider plugin at `plugins/memory/honcho/`. See [Memory Providers](../user-guide/features/memory-providers.md) for installation and usage.
 :::
 
 ## `image_gen` toolset