fix(client): cold-start round 2 — DERIVING TERRAIN state, legend re-fit, release server for make atlas

Item 1: while zero tiles have arrived, the viewer draws a centered
screen-space 'DERIVING TERRAIN…' label (text_dim role, no new hue),
dropping the instant the first tile lands — a cold wait now reads as
loading, not broken. New has_any_tile_arrived() predicate (distinct
from has_pending_tiles(): both true mid-arrival, tested exactly there).

Item 2: legend re-fit root-caused empirically, two plausible fixes
disproven by trace before the real one: a manually-positioned Control's
size NEVER tracks a shrinking minimum in this parenting shape, and
RichTextLabel.fit_content reports degenerate minimums until laid out at
real width once — so reset must be DEFERRED and run after refill, not
inside clear(). ImplantPanel.reset_to_content_size() (call_deferred),
wired into both legend refresh()es. The load-bearing test compares
size.y to get_minimum_size().y — a size-to-size comparison passed
trivially with both numbers equally stuck (caught on first draft).

Item 3: make atlas now builds the RELEASE server and passes
SR_SERVER_BIN (a cold DEBUG server delivers zero tiles for >10s on a
new body — live-measured — vs 210ms warm; release serves cold in well
under a second). atlas_standalone._server_binary_path() honors the env
override per the SR_PORT two-tier precedent, debug path unchanged
when unset.

All fixes revert-verified; nine suites green collateral-checked;
gdlint clean.

Makefile

@@ -126,6 +126,9 @@ build: build-server build-client
 build-server:
 	cd server && cargo build
 
+build-server-release:
+	cd server && cargo build --release
+
 build-client:
 	@test -n "$(GODOT)" || { echo "Godot not found. Run 'make setup' first."; exit 1; }
 	@# First import may error on theme/font loading before the import scan completes.
@@ -161,9 +164,14 @@ game: stop build
 # without it SimBridge boots in test mode (instant fake CONNECTED, no network
 # at all), which would make the companion open the Atlas against a dynamic
 # test-harness snapshot instead of the real systems.db world via the wire.
-atlas: build-server build-client
+# Release server for the atlas: a cold DEBUG server takes >10s before the
+# first tile of a new body can exist (first-body terrain analysis), which
+# reads as a black/broken map on entry (live-verified 2026-07-22). The
+# release binary serves a cold body's first tiles in well under a second.
+# SR_SERVER_BIN tells atlas_standalone.gd's spawn path which binary to use.
+atlas: build-server-release build-client
 	@test -n "$(GODOT)" || { echo "Godot not found. Run 'make setup' first."; exit 1; }
-	@SR_LIVE=1 $(GODOT) --path client scenes/atlas_standalone.tscn
+	@SR_LIVE=1 SR_SERVER_BIN=server/target/release/settled-reach-server $(GODOT) --path client scenes/atlas_standalone.tscn
 
 stop:
 	@lsof -ti :9876 | xargs -r kill 2>/dev/null || true