Prepare the 0.6.0 release

[nickschuetz]

What

Prepares the 0.6.0 release:

• rolls the Unreleased changelog into a 0.6.0 section (2026-10-09);
• bumps the version;
• replaces the pre-release wording "gem main or 0.6.0+" with "gem 0.6.0+" in the docs, docstrings and test skip messages, now that AiCompanion gem 0.6.0 is out.

0.6.0 pairs with AiCompanion gem 0.6.0 (API 0.5.0), which the animation, asset readiness and native scale features need. The total is 96 tools.

Since 0.5.0

• EMotion FX anim graph reads and authoring: 17 tools (graphs, nodes, states, parameters, transitions with conditions, blend-tree ports).
• Per-asset readiness: wait_for_asset, get_asset_status, get_asset_jobs (with failure logs) and get_asset_processor_connection.
• set_transform: real non-uniform scale and native quaternions on gem API 0.5.0; on older gems, a refusal instead of a silent wrong scale.
• One failure envelope ({"status": "error", "code", "message"}) across every tool.
• Entity ids that survive 64-bit values, are accepted as a number, a digit string or [1234], and are looked up rather than rebuilt.
• Fixes for tools that reported success for things that did not happen:
  • assign_asset, set_transform, the component property tools;
  • get_cvar, add_component, and instantiate_prefab's parent.
• The asset tools now work on real projects: user/log, the installed-SDK AssetProcessorBatch, and the export timeout.

Release gates

• Full documentation audit, with its findings fixed in Fix what the pre-release audit found, in code and docs #37.
• Live editor suite, 58 passed, against the released AiCompanion gem 0.6.0 (54798a4, the tree that was tagged).
• Static gates and 650 unit tests.
• python -m build and twine check pass.
• A clean-install smoke test whose MCP handshake reports o3de-mcp 0.6.0 with 96 tools.