mopac-pdf v0: markdown to beautiful PDFs via digest-pinned typst

Go CLI that turns the markdown currency of this stack (Redmine notes,
Discourse posts, briefing output) into typeset PDFs: two embedded typst
templates (report with title page/TOC/headers, dense brief), front-matter
(title/subtitle/author/date/classification/template), GFM tables, and
bar charts rendered in pure Go (go-chart) from fenced chart data blocks.
Engine is a prebuilt typst 0.15.1 container pinned by digest and run
--network none; PDF bytes to stdout or -o. Exit codes 0/1/2.

All dev in docker (dev.sh/Makefile); unit tests + golden typst fixtures
plus a host-side smoke against the real engine container.

Generated with Crush

Assisted-by: Crush:glm-5.2

vendor/github.com/wcharczuk/go-chart/v2/linear_coefficient_provider.go

@@ -0,0 +1,42 @@
+package chart
+
+// LinearCoefficientProvider is a type that returns linear cofficients.
+type LinearCoefficientProvider interface {
+	Coefficients() (m, b, stdev, avg float64)
+}
+
+// LinearCoefficients returns a fixed linear coefficient pair.
+func LinearCoefficients(m, b float64) LinearCoefficientSet {
+	return LinearCoefficientSet{
+		M: m,
+		B: b,
+	}
+}
+
+// NormalizedLinearCoefficients returns a fixed linear coefficient pair.
+func NormalizedLinearCoefficients(m, b, stdev, avg float64) LinearCoefficientSet {
+	return LinearCoefficientSet{
+		M:      m,
+		B:      b,
+		StdDev: stdev,
+		Avg:    avg,
+	}
+}
+
+// LinearCoefficientSet is the m and b values for the linear equation in the form:
+// y = (m*x) + b
+type LinearCoefficientSet struct {
+	M      float64
+	B      float64
+	StdDev float64
+	Avg    float64
+}
+
+// Coefficients returns the coefficients.
+func (lcs LinearCoefficientSet) Coefficients() (m, b, stdev, avg float64) {
+	m = lcs.M
+	b = lcs.B
+	stdev = lcs.StdDev
+	avg = lcs.Avg
+	return
+}