feat(rah-light): replace workflows with guides system

- Remove entire workflow system (API routes, services, tools, components)
- Add guides system from main ra-h repo (for external agent integration)
- Update pane types: 'workflows' → 'guides' throughout
- Update LeftToolbar to show guides icon instead of workflows
- Update SettingsModal with GuidesViewer tab
- Add GuidesPane for browsing guides in main UI
- Clean up prompts to remove workflow references
- Update tool registry to remove workflow tools
- Add gray-matter package for frontmatter parsing

Guides are essential for RA-H Light as they help external agents
(via MCP) understand the knowledge base context and usage patterns.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/config/guides/survey.md

@@ -0,0 +1,53 @@
+---
+name: Survey
+description: Survey a dimension — analyze patterns, themes, gaps, and insights across all nodes within it.
+---
+
+# Survey
+
+Analyze the active dimension to identify patterns, themes, gaps, and insights across all nodes within it.
+
+**Prerequisite:** This guide requires an active dimension. Check the ACTIVE DIMENSION section in context.
+
+## Steps
+
+1. **Retrieve Dimension Nodes**
+   - Call `queryDimensionNodes` with the active dimension name
+   - Set limit to 50 to get a comprehensive view
+   - Note the total count and most connected nodes
+
+2. **Analyze Themes**
+   - Call `searchContentEmbeddings` with key concepts from the dimension
+   - Identify recurring themes, patterns, and relationships
+   - Note any gaps or underrepresented areas
+
+3. **Document Findings**
+   Call `updateDimension` to update the dimension description with:
+
+   ```
+   **Survey Summary**
+
+   **Node Count:** [X nodes]
+   **Top Hubs:** [List 3-5 most connected nodes with [NODE:id:"title"]]
+
+   **Themes:**
+   - [Theme 1 — brief description]
+   - [Theme 2 — brief description]
+
+   **Gaps/Opportunities:**
+   - [Identified gap or area for expansion]
+
+   **Connections to Other Dimensions:**
+   - [Any cross-dimension patterns observed]
+   ```
+
+4. **Return Summary**
+   Reply with: "Surveyed [dimension] — [X nodes, key insight in <15 words]"
+
+## Rules
+
+- Keep total tool calls ≤ 5
+- Focus on patterns across the dimension, not individual node details
+- Identify both strengths (dense areas) and gaps (sparse areas)
+- Reference specific nodes using `[NODE:id:"title"]` format
+- If no active dimension is set, inform the user to open a dimension folder first