feat: triple-toggle CPU display mode via 1 key; add tooltip, font, hit-test

CPU display now cycles through three states with each press of 1:
  0 = CPUModeAverage  – aggregate bar only (default)
  1 = CPUModeCores    – individual core bars + aggregate
  2 = CPUModeOff      – all CPU bars hidden

Config file stores cpumode=N (integer); old showcores=0/1 is read for
backward compatibility. CLI flag --showcores replaced by --cpumode.

Other improvements landed in this commit:
- internal/display: add font.go (text rendering), hittest.go (bar hit
  testing), tooltip.go (mouse-over tooltip), tooltip_test.go
- internal/display: mouse tracking and drawOverlay hook in display.go
- internal/display: update build tags to //go:build form
- internal/collector: embed remote script via script_embed.go /
  scriptdata/loadbars-remote.sh
- internal/collector: CPULine.Total() changed to value receiver
- internal/collector: table test improvements (name field, t.Run)
- internal/constants: BytesPerSec consts promoted from var to const
- Magefile.go: fix error formatting and install path

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

1 files changed, 248 insertions, 0 deletions

diff --git a/internal/display/font.go b/internal/display/font.go
new file mode 100644
index 0000000..d6dae18
--- /dev/null
+++ b/internal/display/font.go
@@ -0,0 +1,248 @@
+package display
+
+import "github.com/veandco/go-sdl2/sdl"
+
+// Bitmap font: 5x7 pixel glyphs for ASCII 32–126, rendered via FillRect.
+// Each glyph is 7 rows of 5 bits (MSB = leftmost pixel).
+
+const (
+	glyphW = 5 // pixels per character width
+	glyphH = 7 // pixels per character height
+	charGap = 1 // horizontal gap between characters
+)
+
+// font5x7 maps ASCII 32–126 to 7-byte bitmaps (one byte per row, top 5 bits used).
+// Index 0 = space (0x20), index 94 = tilde (0x7E).
+var font5x7 = [95][7]byte{
+	// space (0x20)
+	{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
+	// ! (0x21)
+	{0x20, 0x20, 0x20, 0x20, 0x20, 0x00, 0x20},
+	// " (0x22)
+	{0x50, 0x50, 0x00, 0x00, 0x00, 0x00, 0x00},
+	// # (0x23)
+	{0x50, 0xF8, 0x50, 0x50, 0x50, 0xF8, 0x50},
+	// $ (0x24)
+	{0x20, 0x70, 0xA0, 0x70, 0x28, 0x70, 0x20},
+	// % (0x25)
+	{0xC8, 0xC8, 0x10, 0x20, 0x40, 0x98, 0x98},
+	// & (0x26)
+	{0x40, 0xA0, 0xA0, 0x40, 0xA8, 0x90, 0x68},
+	// ' (0x27)
+	{0x20, 0x20, 0x00, 0x00, 0x00, 0x00, 0x00},
+	// ( (0x28)
+	{0x10, 0x20, 0x40, 0x40, 0x40, 0x20, 0x10},
+	// ) (0x29)
+	{0x40, 0x20, 0x10, 0x10, 0x10, 0x20, 0x40},
+	// * (0x2A)
+	{0x00, 0x20, 0xA8, 0x70, 0xA8, 0x20, 0x00},
+	// + (0x2B)
+	{0x00, 0x20, 0x20, 0xF8, 0x20, 0x20, 0x00},
+	// , (0x2C)
+	{0x00, 0x00, 0x00, 0x00, 0x00, 0x20, 0x40},
+	// - (0x2D)
+	{0x00, 0x00, 0x00, 0xF8, 0x00, 0x00, 0x00},
+	// . (0x2E)
+	{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x20},
+	// / (0x2F)
+	{0x08, 0x08, 0x10, 0x20, 0x40, 0x80, 0x80},
+	// 0 (0x30)
+	{0x70, 0x88, 0x98, 0xA8, 0xC8, 0x88, 0x70},
+	// 1 (0x31)
+	{0x20, 0x60, 0x20, 0x20, 0x20, 0x20, 0x70},
+	// 2 (0x32)
+	{0x70, 0x88, 0x08, 0x10, 0x20, 0x40, 0xF8},
+	// 3 (0x33)
+	{0x70, 0x88, 0x08, 0x30, 0x08, 0x88, 0x70},
+	// 4 (0x34)
+	{0x10, 0x30, 0x50, 0x90, 0xF8, 0x10, 0x10},
+	// 5 (0x35)
+	{0xF8, 0x80, 0xF0, 0x08, 0x08, 0x88, 0x70},
+	// 6 (0x36)
+	{0x30, 0x40, 0x80, 0xF0, 0x88, 0x88, 0x70},
+	// 7 (0x37)
+	{0xF8, 0x08, 0x10, 0x20, 0x40, 0x40, 0x40},
+	// 8 (0x38)
+	{0x70, 0x88, 0x88, 0x70, 0x88, 0x88, 0x70},
+	// 9 (0x39)
+	{0x70, 0x88, 0x88, 0x78, 0x08, 0x10, 0x60},
+	// : (0x3A)
+	{0x00, 0x00, 0x20, 0x00, 0x00, 0x20, 0x00},
+	// ; (0x3B)
+	{0x00, 0x00, 0x20, 0x00, 0x00, 0x20, 0x40},
+	// < (0x3C)
+	{0x08, 0x10, 0x20, 0x40, 0x20, 0x10, 0x08},
+	// = (0x3D)
+	{0x00, 0x00, 0xF8, 0x00, 0xF8, 0x00, 0x00},
+	// > (0x3E)
+	{0x80, 0x40, 0x20, 0x10, 0x20, 0x40, 0x80},
+	// ? (0x3F)
+	{0x70, 0x88, 0x08, 0x10, 0x20, 0x00, 0x20},
+	// @ (0x40)
+	{0x70, 0x88, 0xB8, 0xA8, 0xB8, 0x80, 0x70},
+	// A (0x41)
+	{0x70, 0x88, 0x88, 0xF8, 0x88, 0x88, 0x88},
+	// B (0x42)
+	{0xF0, 0x88, 0x88, 0xF0, 0x88, 0x88, 0xF0},
+	// C (0x43)
+	{0x70, 0x88, 0x80, 0x80, 0x80, 0x88, 0x70},
+	// D (0x44)
+	{0xF0, 0x88, 0x88, 0x88, 0x88, 0x88, 0xF0},
+	// E (0x45)
+	{0xF8, 0x80, 0x80, 0xF0, 0x80, 0x80, 0xF8},
+	// F (0x46)
+	{0xF8, 0x80, 0x80, 0xF0, 0x80, 0x80, 0x80},
+	// G (0x47)
+	{0x70, 0x88, 0x80, 0xB8, 0x88, 0x88, 0x70},
+	// H (0x48)
+	{0x88, 0x88, 0x88, 0xF8, 0x88, 0x88, 0x88},
+	// I (0x49)
+	{0x70, 0x20, 0x20, 0x20, 0x20, 0x20, 0x70},
+	// J (0x4A)
+	{0x38, 0x10, 0x10, 0x10, 0x10, 0x90, 0x60},
+	// K (0x4B)
+	{0x88, 0x90, 0xA0, 0xC0, 0xA0, 0x90, 0x88},
+	// L (0x4C)
+	{0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0xF8},
+	// M (0x4D)
+	{0x88, 0xD8, 0xA8, 0xA8, 0x88, 0x88, 0x88},
+	// N (0x4E)
+	{0x88, 0xC8, 0xA8, 0x98, 0x88, 0x88, 0x88},
+	// O (0x4F)
+	{0x70, 0x88, 0x88, 0x88, 0x88, 0x88, 0x70},
+	// P (0x50)
+	{0xF0, 0x88, 0x88, 0xF0, 0x80, 0x80, 0x80},
+	// Q (0x51)
+	{0x70, 0x88, 0x88, 0x88, 0xA8, 0x90, 0x68},
+	// R (0x52)
+	{0xF0, 0x88, 0x88, 0xF0, 0xA0, 0x90, 0x88},
+	// S (0x53)
+	{0x70, 0x88, 0x80, 0x70, 0x08, 0x88, 0x70},
+	// T (0x54)
+	{0xF8, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20},
+	// U (0x55)
+	{0x88, 0x88, 0x88, 0x88, 0x88, 0x88, 0x70},
+	// V (0x56)
+	{0x88, 0x88, 0x88, 0x88, 0x88, 0x50, 0x20},
+	// W (0x57)
+	{0x88, 0x88, 0x88, 0xA8, 0xA8, 0xD8, 0x88},
+	// X (0x58)
+	{0x88, 0x88, 0x50, 0x20, 0x50, 0x88, 0x88},
+	// Y (0x59)
+	{0x88, 0x88, 0x50, 0x20, 0x20, 0x20, 0x20},
+	// Z (0x5A)
+	{0xF8, 0x08, 0x10, 0x20, 0x40, 0x80, 0xF8},
+	// [ (0x5B)
+	{0x70, 0x40, 0x40, 0x40, 0x40, 0x40, 0x70},
+	// \ (0x5C)
+	{0x80, 0x80, 0x40, 0x20, 0x10, 0x08, 0x08},
+	// ] (0x5D)
+	{0x70, 0x10, 0x10, 0x10, 0x10, 0x10, 0x70},
+	// ^ (0x5E)
+	{0x20, 0x50, 0x88, 0x00, 0x00, 0x00, 0x00},
+	// _ (0x5F)
+	{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF8},
+	// ` (0x60)
+	{0x40, 0x20, 0x00, 0x00, 0x00, 0x00, 0x00},
+	// a (0x61)
+	{0x00, 0x00, 0x70, 0x08, 0x78, 0x88, 0x78},
+	// b (0x62)
+	{0x80, 0x80, 0xF0, 0x88, 0x88, 0x88, 0xF0},
+	// c (0x63)
+	{0x00, 0x00, 0x70, 0x80, 0x80, 0x80, 0x70},
+	// d (0x64)
+	{0x08, 0x08, 0x78, 0x88, 0x88, 0x88, 0x78},
+	// e (0x65)
+	{0x00, 0x00, 0x70, 0x88, 0xF8, 0x80, 0x70},
+	// f (0x66)
+	{0x30, 0x48, 0x40, 0xE0, 0x40, 0x40, 0x40},
+	// g (0x67)
+	{0x00, 0x00, 0x78, 0x88, 0x78, 0x08, 0x70},
+	// h (0x68)
+	{0x80, 0x80, 0xF0, 0x88, 0x88, 0x88, 0x88},
+	// i (0x69)
+	{0x20, 0x00, 0x60, 0x20, 0x20, 0x20, 0x70},
+	// j (0x6A)
+	{0x10, 0x00, 0x30, 0x10, 0x10, 0x90, 0x60},
+	// k (0x6B)
+	{0x80, 0x80, 0x90, 0xA0, 0xC0, 0xA0, 0x90},
+	// l (0x6C)
+	{0x60, 0x20, 0x20, 0x20, 0x20, 0x20, 0x70},
+	// m (0x6D)
+	{0x00, 0x00, 0xD0, 0xA8, 0xA8, 0xA8, 0xA8},
+	// n (0x6E)
+	{0x00, 0x00, 0xF0, 0x88, 0x88, 0x88, 0x88},
+	// o (0x6F)
+	{0x00, 0x00, 0x70, 0x88, 0x88, 0x88, 0x70},
+	// p (0x70)
+	{0x00, 0x00, 0xF0, 0x88, 0xF0, 0x80, 0x80},
+	// q (0x71)
+	{0x00, 0x00, 0x78, 0x88, 0x78, 0x08, 0x08},
+	// r (0x72)
+	{0x00, 0x00, 0xB0, 0xC8, 0x80, 0x80, 0x80},
+	// s (0x73)
+	{0x00, 0x00, 0x78, 0x80, 0x70, 0x08, 0xF0},
+	// t (0x74)
+	{0x40, 0x40, 0xE0, 0x40, 0x40, 0x48, 0x30},
+	// u (0x75)
+	{0x00, 0x00, 0x88, 0x88, 0x88, 0x88, 0x78},
+	// v (0x76)
+	{0x00, 0x00, 0x88, 0x88, 0x88, 0x50, 0x20},
+	// w (0x77)
+	{0x00, 0x00, 0x88, 0x88, 0xA8, 0xA8, 0x50},
+	// x (0x78)
+	{0x00, 0x00, 0x88, 0x50, 0x20, 0x50, 0x88},
+	// y (0x79)
+	{0x00, 0x00, 0x88, 0x88, 0x78, 0x08, 0x70},
+	// z (0x7A)
+	{0x00, 0x00, 0xF8, 0x10, 0x20, 0x40, 0xF8},
+	// { (0x7B)
+	{0x10, 0x20, 0x20, 0x40, 0x20, 0x20, 0x10},
+	// | (0x7C)
+	{0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20},
+	// } (0x7D)
+	{0x40, 0x20, 0x20, 0x10, 0x20, 0x20, 0x40},
+	// ~ (0x7E)
+	{0x00, 0x00, 0x40, 0xA8, 0x10, 0x00, 0x00},
+}
+
+// drawChar renders a single ASCII character at (x, y) using filled rectangles.
+// Each pixel of the 5x7 glyph is drawn as a scale×scale block.
+func drawChar(renderer *sdl.Renderer, ch byte, x, y, scale int32) {
+	if ch < 0x20 || ch > 0x7E {
+		ch = '?' // replace unprintable characters
+	}
+	glyph := font5x7[ch-0x20]
+	for row := 0; row < glyphH; row++ {
+		bits := glyph[row]
+		for col := 0; col < glyphW; col++ {
+			if bits&(0x80>>uint(col)) != 0 {
+				renderer.FillRect(&sdl.Rect{
+					X: x + int32(col)*scale,
+					Y: y + int32(row)*scale,
+					W: scale,
+					H: scale,
+				})
+			}
+		}
+	}
+}
+
+// drawString renders a string at (x, y) with the given pixel scale.
+// Returns the total width in pixels consumed by the string.
+func drawString(renderer *sdl.Renderer, s string, x, y, scale int32) int32 {
+	cx := x
+	for i := 0; i < len(s); i++ {
+		drawChar(renderer, s[i], cx, y, scale)
+		cx += (glyphW + charGap) * scale
+	}
+	return cx - x
+}
+
+// stringWidth returns the pixel width of a string at the given scale.
+func stringWidth(s string, scale int32) int32 {
+	if len(s) == 0 {
+		return 0
+	}
+	return int32(len(s))*(glyphW+charGap)*scale - charGap*scale
+}