Add owl sign-in page for the G2 run screen

First UI for the ops team: a local sign-in page where an owl sits on
the card, watches the password field as you type, shakes its head on
a wrong password and hops on the right one. Uses a test password for
now; where the real G2 password lives is still undecided.

Also adds PRODUCT.md (product context for UI work) and the page's
design brief under .impeccable/surfaces/.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.impeccable/surfaces/src-ui-login-html.md

@@ -0,0 +1,24 @@
+---
+version: 1
+slug: "src-ui-login-html"
+primary_target: "src/ui/login.html"
+related_targets: []
+---
+
+## Scope
+
+Operate. G2 sign-in page for the ops team, first build only: owl, password field, show/hide, sign in, test password, placeholder "run screen coming soon" after sign-in. Real password storage, lockout, per-person usernames and the run screen are undecided and out of scope.
+
+## Direction contract
+
+THESIS: A sign-in the owl watches. Refuses the faceless centered form with a logo above it: the owl sits on the card and reacts to what you type.
+
+OWN-WORLD: The user's pinned world, rendered natural, not game-like (user, 22 Oct: no pixel look). Deep navy night ground (#040b26) with small soft round stars (blue, teal, orange, white). A smooth, softly shaded orange owl like the user's reference: dome head with ear tufts, egg body, wide cream face disc, big brown eyes behind round black glasses, peach belly, darker wings, small feet. Dark outlined pill controls, like the user's HOOT button, for both the field and the button. Product name and all text in the platform UI face; standard stroke eye icon.
+
+STORY: The ops user sees the owl, types the G2 password, and the owl's eyes follow the typing. A wrong password makes the owl shake its head no and the text says what to do. The right one makes it hop and lets them in.
+
+FIRST VIEWPORT: Centered column. Product name "Charge Billed Automation", then the card with the owl perched on its top edge (feet on the border), password field with show/hide, full-width pill Sign in. The night sky fills the viewport.
+
+FORM: Pinned by the user (owl screenshot); no roll was run. seed: none (user-pinned direction)
+
+FINISH: unreviewed and undocumented is unfinished; this build ends with the finish review, the verdict, DESIGN.md, and every shipping raster carrying its provenance