What is G_N? From "Underivable" to the Exchange Rate between Information and Geometry

A Perspective article arguing that Newton's constant G_N cannot have its numerical value derived from dimensionless data (a dimensional-analysis trichotomy), while its identity is nevertheless clear: G_N is the exchange rate between information and geometry — the area price of one bit — anchored at their seam, in exact parallel to the speed of light c. The argument traverses an eight-link chain, takes the Brown-Henneaux relation as its theorem-level anchor, and stitches the G_N problem and the cosmological-constant problem into a single counting problem. All conclusions are graded by evidential strength (Tier A theorem / Tier B literature / Tier C conceptual analogy).