initial: actor v0.1.0 — composition-wrapper + movement-speed-contract

Phase-A.5 implementation per
sporel-meta/docs/superpowers/specs/2026-06-09-phase-A-...
Re-Entry from P.0-Actor-Deferral (Trigger 1: Composition-Aktivierung).

Slim wrapper: actor.create validates properties.movement_speed > 0,
delegates to composition.create. actor.position reads dotted position
back as two numbers. actor.move does direct inert-write to position.x
+ position.y (engine §11 inert-write; Action-routing deferred).

DEFERRED in v0.1: Body-Slot-Aggregator, Walk-Capability, Movement-State
on entity, Action-mediated move. All have re-entry-trigger notes.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

init.lua

@@ -0,0 +1,86 @@
+-- =====================================================================
+-- lib-core.actor v0.1.0 — Position + Movement-Speed wrapper over composition
+-- See: meta/docs/superpowers/specs/2026-06-09-phase-A-inactive-entities-...
+--
+-- v0.1.0 Spine-Cut:
+--   - actor.create(spec) — validates 'properties.movement_speed' is set
+--     (positive number) then delegates to composition.create. Caller is
+--     responsible for composition.define_template{id=<template>, ...}
+--     before invoking; actor doesn't auto-define templates.
+--   - actor.position(handle) -> x, y — convenience read for the
+--     dotted position-properties.
+--   - actor.move(handle, dx, dy) — direct inert-write to position.x /
+--     position.y. dt-scaling is the caller's job (typically
+--     player_control multiplies dx/dy by movement_speed * dt before
+--     calling).
+--
+-- DEFERRED (no consumer yet — wait for re-entry trigger):
+--   - Body-Slot-Aggregator         → Phase D / J trigger
+--   - Walk-Capability (per ADR-0002)→ second-actor-consumer trigger
+--   - Movement-State on the entity → kept ephemeral in player_control
+--   - Action-mediated move          → when "move" Action exists and
+--                                     event/effect routing matters
+--                                     (engine-primitives §11 inert-write
+--                                     is the v0.1 escape hatch)
+-- =====================================================================
+
+local composition = require("lib-core.composition")
+
+local M = {}
+
+function M.create(spec)
+    if type(spec) ~= "table" then
+        error("actor.create: expected table, got " .. type(spec))
+    end
+    if type(spec.properties) ~= "table" then
+        error("actor.create: 'properties' table is required " ..
+              "(must contain at least 'movement_speed' and 'position')")
+    end
+    local ms = spec.properties.movement_speed
+    if type(ms) ~= "number" or ms <= 0 then
+        error("actor.create: 'properties.movement_speed' must be a positive " ..
+              "number (got " .. tostring(ms) .. "); actors need a baseline " ..
+              "speed; callers typically apply dt-scaling before actor.move")
+    end
+    -- composition.create handles position-flattening + template-lookup
+    -- + tag-index registration. We don't add anything else here in v0.1;
+    -- this wrapper exists primarily to enforce the movement_speed
+    -- contract and to mark the entity as an "actor" semantically for
+    -- future Phase-D extensions.
+    return composition.create(spec)
+end
+
+function M.position(handle)
+    if handle == nil then
+        error("actor.position: handle must not be nil")
+    end
+    local x = handle:get_property("position.x")
+    local y = handle:get_property("position.y")
+    return x, y
+end
+
+-- Direct inert-write to position.x / position.y. Use composition's already-
+-- declared inert properties; no Action-routing in v0.1 (see DEFERRED note).
+function M.move(handle, dx, dy)
+    if handle == nil then
+        error("actor.move: handle must not be nil")
+    end
+    if type(dx) ~= "number" or type(dy) ~= "number" then
+        error("actor.move: dx and dy must be numbers")
+    end
+    local x = handle:get_property("position.x")
+    local y = handle:get_property("position.y")
+    handle:set_property("position.x", x + dx)
+    handle:set_property("position.y", y + dy)
+end
+
+-- Convenience: read the actor's movement_speed property (in pixels/sec
+-- by convention; caller decides what "pixel" means).
+function M.movement_speed(handle)
+    if handle == nil then
+        error("actor.movement_speed: handle must not be nil")
+    end
+    return handle:get_property("movement_speed")
+end
+
+return M