Add new tests and implement frame budget management

- Introduced `civilization_benchmark.gd` and `legacy_quantity_math.gd` for benchmarking and legacy quantity calculations.
- Created `test_dynamic_math.gd`, `test_frame_evolution.gd`, and `test_sparse_batches.gd` to validate mathematical operations and frame evolution logic.
- Implemented `frame_budget.gd` to manage cooperative work on the main thread, ensuring no partially calculated state is published.
- Added UID files for all new scripts to maintain unique identifiers.

tests/fixtures/benchmark_ui_stage.gd

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+extends "res://stage/stage.gd"
+
+var measuring: bool = false
+var process_samples: Array = []
+var frame_samples: Array = []
+var previous_frame: int = 0
+
+# Exercise the production Stage, with isolated state and no player-save I/O.
+func load_data() -> bool: return false
+func save_data() -> void: pass
+func _notification(_what: int) -> void: pass
+
+func _process(delta: float) -> void:
+    if not measuring: return
+    var started: int = Time.get_ticks_usec()
+    if previous_frame: frame_samples.append((started - previous_frame) / 1000.0)
+    previous_frame = started
+    super._process(delta)
+    process_samples.append((Time.get_ticks_usec() - started) / 1000.0)

tests/fixtures/benchmark_ui_stage.gd.uid

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+uid://d1wm7nav71y3o

tests/fixtures/civilization_benchmark.gd

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+extends RefCounted
+const E = preload("res://world/owniverse/math/exact.gd")
+
+static func seed(world, global, fragmented: bool = false, large: bool = false, stable: bool = false):
+    for id in world.catalog.entities:
+        world.state.amount[id] = 0
+        world.state.stats.total_amount[id] = 0
+        var entity = world.catalog.entities[id]
+        if entity.group_as != "":
+            world.state.amount[entity.group_as] = 0
+            world.state.stats.total_amount[entity.group_as] = 0
+    for id in ["RD", "BG", "TWD", "SNS", "MGT", "BH25", "SMBH", "SCD", "GEM", "LGG", "LSC", "LGF", "LGW", "LUB"]:
+        world.state.amount[id] = E.of("1e48")
+    world.state.amount.S = E.of("1e50")
+    world.state.amount.H = E.of("1e48")
+    world.state.binds.RD = {"HP": E.of("1e30"), "RP": E.of("1e30"), "GG": E.of("1e30"), "AB": E.of("1e30")}
+    var count = E.of("6e20") if large else 6000
+    for id in global.CivilizationRules:
+        if E.le(global.CivilizationRules[id].span, 0): continue
+        world.state.amount[id] = count
+        world.state.ethics[id] = {}
+        for ethic in ["m", "l", "w", "d", "c", "b"]:
+            world.state.ethics[id][ethic] = E.divide(count, 6)
+        world.state.batches[id] = []
+        var parties: int = 10 if fragmented else 1
+        for i in parties:
+            var lifespan = E.of(global.CivilizationRules[id].span) if stable else 1
+            world.state.batches[id].append({"amount": E.divide(count, parties), "created_from": i * 100, "created_to": 1000 + i * 100, "start_year": E.add(lifespan, i * 100), "end_year": E.add(lifespan, 1000 + i * 100)})
+    world.ledger.refresh_groups(world.state)
+    world.speed = 6

tests/fixtures/civilization_benchmark.gd.uid

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+uid://bjloakx4qdpsj

tests/fixtures/legacy_quantity_math.gd

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+extends RefCounted
+const E = preload("res://world/owniverse/math/exact.gd")
+# Frozen apportionment before the civilization performance refactor.
+
+static func allocate_whole(requests: Dictionary, limit: Variant) -> Dictionary:
+    var total: Variant = 0
+    for amount in requests.values():
+        total = E.add(total, E.floor_value(E.maximum(0, amount)))
+    var available: Variant = E.floor_value(E.minimum(E.maximum(0, limit), total))
+    var result: Dictionary = {}
+    var order: Array = []
+    var assigned: Variant = 0
+    for id in requests:
+        var expected: Variant = (E.mul_div(E.floor_value(E.maximum(0, requests[id])), available, total) if E.gt(total, 0) else 0)
+        result[id] = E.floor_value(expected)
+        assigned = E.add(assigned, result[id])
+        order.append({"id": id, "rest": E.subtract(expected, result[id])})
+    order.sort_custom(func ( a : Dictionary , b : Dictionary ) -> bool : return (E.gt(a.rest, b.rest) if E.ne(a.rest, b.rest) else E.lt(str(a.id), str(b.id))))
+    for item : Dictionary in order:
+        if E.ge(assigned, available):
+            break
+        if E.lt(result[item.id], E.floor_value(requests[item.id])):
+            result[item.id] = E.add(result[item.id], 1)
+            assigned = E.add(assigned, 1)
+    return result
+
+
+static func sum(pop: Dictionary) -> Variant:
+    var result: Variant = 0
+    for n in pop.values(): result = E.add(result, n)
+    return result
+
+
+static func split(remainders: Dictionary, key: String, count: Variant, weights: Dictionary) -> Dictionary:
+    var result: Dictionary = {}
+    var sum_weights: Variant = sum(weights)
+    if (E.le(count, 0) or E.le(sum_weights, 0)): return result
+    var expected: Dictionary = {}
+    var positive_sum: Variant = 0
+    for id in weights:
+        expected[id] = E.add(E.mul_div(count, weights[id], sum_weights), remainders.get(E.add(E.add(key, ":"), id), 0))
+        positive_sum = E.add(positive_sum, E.maximum(0, expected[id]))
+    var order: Array = []
+    var assigned: Variant = 0
+    for id in weights:
+        var normalized: Variant = (E.mul_div(E.maximum(0, expected[id]), count, positive_sum) if E.gt(positive_sum, 0) else 0)
+        result[id] = E.floor_value(normalized)
+        assigned = E.add(assigned, result[id])
+        order.append({"id": id, "rest": E.subtract(normalized, result[id])})
+    order.sort_custom(func ( a , b ) : return (E.gt(a.rest, b.rest) if E.ne(a.rest, b.rest) else E.lt(str(a.id), str(b.id))))
+    for entry in order:
+        if E.ge(assigned, count): break
+        result[entry.id] = E.add(result[entry.id], 1)
+        assigned = E.add(assigned, 1)
+    for id in weights:
+        remainders[E.add(E.add(key, ":"), id)] = E.clamp_value(E.subtract(expected[id], result[id]), E.neg(1), 1)
+    return result
+
+

tests/fixtures/legacy_quantity_math.gd.uid

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+uid://dxsly3qpyqrjy