docs: update spectrum-ts documentation for v1.5.0

[photon-action-bot]

Documentation Update: spectrum-ts v1.5.0

This PR updates documentation for spectrum-ts based on the v1.5.0 release.

Release Notes

New Features

• Added a spectrum-ts/providers entrypoint, so you can import all built-in providers from one place instead of importing each provider path separately.

Bug Fixes

• Fixed iMessage stream cleanup so closing streams no longer waits forever when the underlying pump is already failing or shutting down.
• Hardened iMessage attachment downloads, reactions, replies, edits, polls, and multipart messages against the newer server event shapes.
• Improved local iMessage attachment handling so messages with delayed attachments are retried briefly before being emitted.

Improvement

• Updated the iMessage remote provider for the newer @photon-ai/advanced-imessage server API.
• Updated maintenance tooling dependencies, including Ultracite and clean-publish. ✨

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Version: 1.5.0

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🤖 This PR was auto-generated by Claude Code via the update-docs action in buildspace.

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