docs(references): port style guides, 24 diagram guides, and 9 templates from opencode

All content ported from borealBytes/opencode under Apache-2.0 license with
attribution headers prepended to each file.

- references/markdown_style_guide.md (~733 lines): full markdown formatting,
  citation, collapsible sections, emoji, Mermaid integration, and template
  selection guide
- references/mermaid_style_guide.md (~458 lines): full Mermaid standards —
  emoji set, classDef color palette, accessibility (accTitle/accDescr),
  theme neutrality (no %%{init}), and diagram type selection table
- references/diagrams/ (24 files): per-type exemplars, tips, and templates
  for all Mermaid diagram types
- templates/ (9 files): PR, issue, kanban, ADR, presentation, how-to,
  status report, research paper, project docs

Source: https://github.com/borealBytes/opencode

scientific-skills/markdown-mermaid-writing/references/diagrams/radar.md

@@ -0,0 +1,59 @@
+<!-- Source: https://github.com/borealBytes/opencode | License: Apache-2.0 | Author: Clayton Young / Superior Byte Works, LLC (Boreal Bytes) -->
+
+# Radar Chart
+
+> **Back to [Style Guide](../mermaid_style_guide.md)** — Read the style guide first for emoji, color, and accessibility rules.
+
+**Syntax keyword:** `radar-beta`
+**Mermaid version:** v11.6.0+
+**Best for:** Multi-dimensional comparisons, skill assessments, performance profiles, competitive analysis
+**When NOT to use:** Time series data (use [XY Chart](xy_chart.md)), simple proportions (use [Pie](pie.md))
+
+> ⚠️ **Accessibility:** Radar charts do **not** support `accTitle`/`accDescr`. Always place a descriptive _italic_ Markdown paragraph directly above the code block.
+
+---
+
+## Exemplar Diagram
+
+_Radar chart comparing two engineering candidates across six core competency areas, showing complementary strengths:_
+
+```mermaid
+radar-beta
+    title Team Skill Assessment
+    axis sys["System Design"], algo["Algorithms"], comms["Communication"], team["Teamwork"], ops["DevOps"], acq["Domain Knowledge"]
+    curve candidate_a["Candidate A"]{4, 3, 5, 5, 2, 3}
+    curve candidate_b["Candidate B"]{2, 5, 3, 3, 5, 4}
+    max 5
+    graticule polygon
+    ticks 5
+    showLegend true
+```
+
+---
+
+## Tips
+
+- Define axes with `axis id["Label"]` — use short labels (1–2 words)
+- Define curves with `curve id["Label"]{val1, val2, ...}` matching axis order
+- Set `max` to normalize all values to the same scale
+- `graticule` options: `circle` (default) or `polygon`
+- `ticks` controls the number of concentric rings (default 5)
+- `showLegend true` adds a legend for multiple curves
+- Keep to **5–8 axes** and **2–4 curves** for readability
+- **Always** pair with a Markdown text description above for screen readers
+
+---
+
+## Template
+
+_Description of what dimensions are being compared across which entities:_
+
+```mermaid
+radar-beta
+    title Your Radar Title
+    axis dim1["Dimension 1"], dim2["Dimension 2"], dim3["Dimension 3"], dim4["Dimension 4"], dim5["Dimension 5"]
+    curve series_a["Series A"]{3, 4, 2, 5, 3}
+    curve series_b["Series B"]{5, 2, 4, 3, 4}
+    max 5
+    showLegend true
+```