v2.1.3 - Official prompt and runtime alignment

Fixed

• Added official Seedream 5.0 Pro 1.5K tier support across CLI validation, documentation, and tests.
• Reject streamed duplicate image content assigned to distinct explicit image_index values, preserving an ambiguous billing lock instead of reporting a false multi-image success.
• Retry cleanup of stale completed request state before the next POST and stop safely when the exclusive state lock cannot be removed.
• Stop treating cancelled, empty, or unrecognized model-selection answers as permission to use Lite.

Prompt and capability alignment

• Added the official normalized 0-999 coordinate contract and <point> / <bbox> syntax for Seedream 5.0 Pro interactive editing.
• Kept classification slugs as agent-side routing metadata instead of sending them to the model; only Core request remains mandatory, while purpose and visual fields are added when relevant.
• Aligned prompt guidance with official concise natural-language, sketch/UI text-following, multi-reference role, and edit-preservation recommendations without truncating or blocking prompts by length.
• Replaced the outdated public-evidence gap with direct official support-matrix, Pro tutorial, interactive-editing, and prompt-guide references.

Documentation and validation

• Updated the skill workflow, Lite/Pro references, CLI reference, execution flow, bilingual READMEs, capability manifest, prompt templates, and changelog.
• Local validation: 168 passed, 1 skipped, 100 subtests passed; skill validation, Pro 1.5K dry-run, compileall, pip check, and git diff --check all passed.
• Main and tag CI passed on Ubuntu, macOS, and Windows with Python 3.10-3.13.
• No real Ark request was issued.