Migrate map-local, item, monster, and global-event Python behavior

[zoeyrose]

Outcome

Eliminate the residual runtime Python domains after generic engines/services are proven, using bounded action definitions or explicit native Go handlers.

Scope and invariants

• Cover portals/exits, puzzles, environmental triggers, item use, monster-specific behavior, connection/message hooks, scheduled/global events, spawn/encounter behavior, and map-local scripts from the manifest.
• Prefer Implement generic map/object triggers and authored action graphs #54 typed triggers/action graphs and existing Go services; create a focused handler only when behavior has durable domain semantics that cannot be expressed safely as data.
• For each explicit handler, define stable inputs, state, authorization, event/effect contract, persistence, bounds, and independent acceptance fixtures.
• Do not grow reflection, dynamic module loading, arbitrary host calls, or a shadow general-purpose scripting API.
• Preserve authored map/item/monster designs and licenses; only the independent runtime implementation is MIT.

Acceptance criteria

• All targeted manifest rows are migrated/retired/blocked explicitly and grouped by domain/location for parallel review.
• Fuzz/property tests cover authored graph/handler inputs, recursion/fan-out, stale objects, map unload, persistence failure, and event storms.
• No production package searches for or dispatches .py files.
• Bespoke handlers have direct unit/scenario coverage and are registered through typed catalogs.
• The residual list feeding Starlark Evaluate residual behavior and add Starlark only if justified #60 contains only genuinely irreducible orchestration, with evidence.

Dependencies and parallelization

Depends on #38, #41, #50, #54 and relevant domain services. Parallelize by behavior family, not by copying directory structure.

Licensing and migration rule

Replacement Go code is MIT and independently implemented. Preserve existing gameplay/content design choices and separately licensed data; do not translate GPL runtime source or tests unless an exact contribution has a documented rights-holder MIT grant.