Migrate player auth docs

[tudddorrr]

No description provided.

[claude]

Documentation Review: PR #64

Nice additions overall - the migration docs are clear, and the error code section is a welcome addition to the HTTP API docs.

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🔴 Admonition closing delimiter indented

In both docs/godot/identifying.mdx and docs/unity/identifying.mdx, the closing ::: of the admonition block was changed to have 2-space indentation. In Docusaurus, admonition closing delimiters must be at column 0. Indenting ::: means the renderer will not recognise it as the closing delimiter, causing the admonition to either not close or render raw text to the user.

Fix: Revert both changes back to unindented :::.

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🔵 Undeclared variables in Unity migration example

In docs/unity/player-authentication.mdx, the OnAuthCallback method references currentPassword and validationLabel without them being declared in the snippet. The Godot equivalent uses @onready annotations to make dependencies explicit. A developer copying this Unity snippet will not know the type of currentPassword or where validationLabel comes from.

Fix: Add field declarations at the top of the snippet, for example: [SerializeField] private TMP_InputField currentPassword; and [SerializeField] private TMP_Text validationLabel;

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No issues found in:

• Description metadata updates (Google Play addition) - accurate
• EMAIL_TAKEN and INVALID_MIGRATION_TARGET error docs - clear and match existing format
• Migration success behaviour - documented correctly for both Unity and Godot
• Cross-references to Steamworks and Google Play Games integration pages - correct