docs: comprehensive documentation audit — fix stale info, expand thin pages, add depth (#5393)

Major changes across 20 documentation pages:

Staleness fixes:
- Fix FAQ: wrong import path (hermes.agent → run_agent)
- Fix FAQ: stale Gemini 2.0 model → Gemini 3 Flash
- Fix integrations/index: missing MiniMax TTS provider
- Fix integrations/index: web_crawl is not a registered tool
- Fix sessions: add all 19 session sources (was only 5)
- Fix cron: add all 18 delivery targets (was only telegram/discord)
- Fix webhooks: add all delivery targets
- Fix overview: add missing MCP, memory providers, credential pools
- Fix all line-number references → use function name searches instead
- Update file size estimates (run_agent ~9200, gateway ~7200, cli ~8500)

Expanded thin pages (< 150 lines → substantial depth):
- honcho.md: 43 → 108 lines — added feature comparison, tools, config, CLI
- overview.md: 49 → 55 lines — added MCP, memory providers, credential pools
- toolsets-reference.md: 57 → 175 lines — added explanations, config examples,
  custom toolsets, wildcards, platform differences table
- optional-skills-catalog.md: 74 → 153 lines — added 25+ missing skills across
  communication, devops, mlops (18!), productivity, research categories
- integrations/index.md: 82 → 115 lines — added messaging, HA, plugins sections
- cron-internals.md: 90 → 195 lines — added job JSON example, lifecycle states,
  tick cycle, delivery targets, script-backed jobs, CLI interface
- gateway-internals.md: 111 → 250 lines — added architecture diagram, message
  flow, two-level guard, platform adapters, token locks, process management
- agent-loop.md: 112 → 235 lines — added entry points, API mode resolution,
  turn lifecycle detail, message alternation rules, tool execution flow,
  callback table, budget tracking, compression details
- architecture.md: 152 → 295 lines — added system overview diagram, data flow
  diagrams, design principles table, dependency chain

Other depth additions:
- context-references.md: added platform availability, compression interaction,
  common patterns sections
- slash-commands.md: added quick commands config example, alias resolution
- image-generation.md: added platform delivery table
- tools-reference.md: added tool counts, MCP tools note
- index.md: updated platform count (5 → 14+), tool count (40+ → 47)

website/docs/user-guide/features/overview.md

@@ -31,15 +31,17 @@ Hermes Agent includes a rich set of capabilities that extend far beyond basic ch
 - **[Browser Automation](browser.md)** — Full browser automation with multiple backends: Browserbase cloud, Browser Use cloud, local Chrome via CDP, or local Chromium. Navigate websites, fill forms, and extract information.
 - **[Vision & Image Paste](vision.md)** — Multimodal vision support. Paste images from your clipboard into the CLI and ask the agent to analyze, describe, or work with them using any vision-capable model.
 - **[Image Generation](image-generation.md)** — Generate images from text prompts using FAL.ai's FLUX 2 Pro model with automatic 2x upscaling via the Clarity Upscaler.
-- **[Voice & TTS](tts.md)** — Text-to-speech output and voice message transcription across all messaging platforms, with four provider options: Edge TTS (free), ElevenLabs, OpenAI TTS, and NeuTTS.
+- **[Voice & TTS](tts.md)** — Text-to-speech output and voice message transcription across all messaging platforms, with five provider options: Edge TTS (free), ElevenLabs, OpenAI TTS, MiniMax, and NeuTTS.
 
 ## Integrations
 
+- **[MCP Integration](mcp.md)** — Connect to any MCP server via stdio or HTTP transport. Access external tools from GitHub, databases, file systems, and internal APIs without writing native Hermes tools. Includes per-server tool filtering and sampling support.
 - **[Provider Routing](provider-routing.md)** — Fine-grained control over which AI providers handle your requests. Optimize for cost, speed, or quality with sorting, whitelists, blacklists, and priority ordering.
 - **[Fallback Providers](fallback-providers.md)** — Automatic failover to backup LLM providers when your primary model encounters errors, including independent fallback for auxiliary tasks like vision and compression.
+- **[Credential Pools](credential-pools.md)** — Distribute API calls across multiple keys for the same provider. Automatic rotation on rate limits or failures.
+- **[Memory Providers](memory-providers.md)** — Plug in external memory backends (Honcho, OpenViking, Mem0, Hindsight, Holographic, RetainDB, ByteRover) for cross-session user modeling and personalization beyond the built-in memory system.
 - **[API Server](api-server.md)** — Expose Hermes as an OpenAI-compatible HTTP endpoint. Connect any frontend that speaks the OpenAI format — Open WebUI, LobeChat, LibreChat, and more.
 - **[IDE Integration (ACP)](acp.md)** — Use Hermes inside ACP-compatible editors such as VS Code, Zed, and JetBrains. Chat, tool activity, file diffs, and terminal commands render inside your editor.
-- **[Honcho Memory](honcho.md)** — AI-native persistent memory for cross-session user modeling and personalization via dialectic reasoning.
 - **[RL Training](rl-training.md)** — Generate trajectory data from agent sessions for reinforcement learning and model fine-tuning.
 
 ## Customization