ui/phase-20: ship-group inspector actions

Eight ship-group operations land on the inspector behind a single
inline-form panel: split, send, load, unload, modernize, dismantle,
transfer, join fleet. Each action either appends a typed command to
the local order draft or surfaces a tooltip explaining the
disabled state. Partial-ship operations emit an implicit
breakShipGroup command before the targeted action so the engine
sees a clean (Break, Action) pair on the wire.

`pkg/calc.BlockUpgradeCost` migrates from
`game/internal/controller/ship_group_upgrade.go` so the calc
bridge can wrap a pure pkg/calc formula; the controller now
imports it. The bridge surfaces the function as
`core.blockUpgradeCost`, which the inspector calls once per ship
block to render the modernize cost preview.

`GameReport.otherRaces` is decoded from the report's player block
(non-extinct, ≠ self) and feeds the transfer-to-race picker. The
planet inspector's stationed-ship rows become clickable for own
groups so the actions panel is reachable from the standard click
flow (the renderer continues to hide on-planet groups).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

ui/frontend/src/api/game-state.ts

@@ -272,6 +272,18 @@ export interface GameReport {
 	incomingShipGroups: ReportIncomingShipGroup[];
 	unidentifiedShipGroups: ReportUnidentifiedShipGroup[];
 	localFleets: ReportLocalFleet[];
+	/**
+	 * otherRaces lists the names of every non-extinct race other than
+	 * the local player, sorted alphabetically. Drawn from the
+	 * `report.player[]` block in the FBS report (each `Player` row
+	 * carries an `extinct` flag). The ship-group inspector consumes
+	 * this list for the "transfer to race" picker; Phase 22's Races
+	 * View reuses the same field so the read shape is stable across
+	 * stages. Empty when the report has no `player` block (boot
+	 * state, history-mode snapshots) or when the local player is the
+	 * only non-extinct race.
+	 */
+	otherRaces: string[];
 }
 
 export async function fetchGameReport(
@@ -405,6 +417,7 @@ function decodeReport(report: Report): GameReport {
 	const raceName = report.race() ?? "";
 	const routes = decodeReportRoutes(report);
 	const localTech = findLocalPlayerTech(report, raceName);
+	const otherRaces = collectOtherRaces(report, raceName);
 	const localShipGroups = decodeLocalShipGroups(report);
 	const otherShipGroups = decodeOtherShipGroups(report);
 	const incomingShipGroups = decodeIncomingShipGroups(report);
@@ -429,6 +442,7 @@ function decodeReport(report: Report): GameReport {
 		incomingShipGroups,
 		unidentifiedShipGroups,
 		localFleets,
+		otherRaces,
 	};
 }
 
@@ -705,6 +719,27 @@ function findLocalPlayerTech(
 	return { drive: 0, weapons: 0, shields: 0, cargo: 0 };
 }
 
+/**
+ * collectOtherRaces walks the `report.player[]` block and returns
+ * the alphabetically-sorted names of every non-extinct race other
+ * than the local player. Used by `GameReport.otherRaces` to back the
+ * ship-group inspector's transfer-to-race picker (Phase 20) and the
+ * Races View list (Phase 22).
+ */
+function collectOtherRaces(report: Report, raceName: string): string[] {
+	const out: string[] = [];
+	for (let i = 0; i < report.playerLength(); i++) {
+		const player = report.player(i);
+		if (player === null) continue;
+		if (player.extinct()) continue;
+		const name = player.name() ?? "";
+		if (name === "" || name === raceName) continue;
+		out.push(name);
+	}
+	out.sort((a, b) => a.localeCompare(b));
+	return out;
+}
+
 /**
  * uuidToHiLo splits the canonical 36-character UUID string
  * (`xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx`) into the two big-endian

ui/frontend/src/api/synthetic-report.ts

@@ -102,6 +102,7 @@ interface SyntheticPlayer {
 	weapons: number;
 	shields: number;
 	cargo: number;
+	extinct?: boolean;
 }
 
 interface SyntheticShipGroup {
@@ -269,9 +270,25 @@ function decodeSyntheticReport(json: unknown): GameReport {
 		incomingShipGroups,
 		unidentifiedShipGroups,
 		localFleets,
+		otherRaces: collectOtherRacesFromSynthetic(root, race),
 	};
 }
 
+function collectOtherRacesFromSynthetic(
+	root: SyntheticReportRoot,
+	raceName: string,
+): string[] {
+	const out: string[] = [];
+	for (const player of root.player ?? []) {
+		if (player.extinct === true) continue;
+		const name = typeof player.name === "string" ? player.name : "";
+		if (name === "" || name === raceName) continue;
+		out.push(name);
+	}
+	out.sort((a, b) => a.localeCompare(b));
+	return out;
+}
+
 function toShipGroupTech(raw: Record<string, number> | undefined): ShipGroupTech {
 	const out: ShipGroupTech = { drive: 0, weapons: 0, shields: 0, cargo: 0 };
 	if (raw === undefined || raw === null) return out;