feat: adopt the new Helmryth mark

[DivyamTalwar]

What this changes

Adopts the new Helmryth mark and regenerates every icon from it.

The mark: a run line halted at a notch, with a hand-set arm seated in it. The thin petrol rule is work running; the heavy vermilion arm is a person set into that run at an angle nothing automatic would have chosen; the notch holds the setting so it cannot drift. It draws the product's one claim as a shape — nothing runs until you answer.

Why SVG rather than the raster it was designed from

Not a stylistic preference. Measuring the source artwork found two problems a vector rebuild removes outright.

Colour had drifted off-brand. The generated artwork carried #C75137 / #1F7C7B, and background removal pushed those further to #D74327 / #007476:

	source	bg-removed	brand
vermilion	#C75137	#D74327	#C44F36
petrol	#1F7C7B	#007476	#167A78
ink	#263646	#1B2E46	#273447

That matters more here than usual: the application uses those two exact values for command and for live signal. A logo carrying different ones fights the UI it sits above.

The wordmark letterforms were damaged — bites out of the H crossbar, chipped corners on the E and L, a white notch in the M. Invisible at thumbnail size, unmissable on a retina display.

Fidelity to the approved artwork

The rebuild is traced, not redrawn. Measured off the source and preserved:

• bar at 66–74% of canvas height
• arm spanning 41–80% horizontally, 23–72% vertically
• arm taper from 170 → 141 units (it is not a true parallelogram, and that hand-cut quality is kept)
• lockup mark-height to cap-height ratio of 2.24

What ships

brand/helmryth-mark.svg        the mark, transparent
brand/helmryth-mark-mono.svg   currentColor — proves it works in one colour
brand/helmryth-tile.svg        app tile, master for all generated icons
brand/helmryth-lockup.svg      mark + wordmark
brand/README.md                usage, colour meanings, rules

build/icon.svg is the master; icon-1024.png, icon.icns, icon.ico and the Electron resource are regenerated from it by pnpm build:icons.

Verification

The generated 1024px icon quantises to exactly three brand values — no drift, which was the whole point:

#F6F1E7  53.9%     #C44F36  4.3%     #167A78  3.3%
corner alpha 0, centre alpha 255   (octagon stays transparent, not black)

pnpm check:brand      exit 0
pnpm check:contrast   exit 0
pnpm check:qa-docs    exit 0

Risk and rollback

Low. Assets only, no product code. 399 bytes of SVG replaces 845 KB of PNG, scales to any size, and recolours through currentColor. Reverting restores the previous icons exactly.