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>

pkg/calc/ship.go

@@ -52,6 +52,17 @@ func WeaponsBlockMass(weapons float64, armament uint) (float64, bool) {
 	return float64(armament+1) * (weapons / 2), true
 }
 
+// Стоимость модернизации одного блока корабля -
+// доля недостающего технологического уровня (1 - currentBlockTech/targetBlockTech),
+// умноженная на массу блока и нормирующий коэффициент 10.
+// Возвращает 0, если масса блока равна нулю или целевой уровень не выше текущего.
+func BlockUpgradeCost(blockMass, currentBlockTech, targetBlockTech float64) float64 {
+	if blockMass == 0 || targetBlockTech <= currentBlockTech {
+		return 0
+	}
+	return (1 - currentBlockTech/targetBlockTech) * 10 * blockMass
+}
+
 func DestructionProbability(
 	attackingWeapons,
 	attackingWeaponsTech,