Polish beta readiness docs and macro guidance

[worflor]

What changed

• Bring release notes, platform status, and the protocol host docs in line with the Windows beta and deferred Linux package.
• Include the README edits, add a direct bug-triage path, and add the Neuron macro skill with BOUND/RAW and beacon guidance.
• Make the contributor summary direct and shorten its PR checkbox without changing the agreement.
• Isolate capture tests that share process-global state; allow the known locally built v0.1.0 asset to report missing provenance after checksum verification. Later releases still require an attestation.

Verification

• Windows: .\validate.ps1 -Mode full -Locked passed, including Clippy with no warnings, release build, feature checks, and the safe ignored tests.
• WSL2: pwsh ./validate.ps1 -Locked passed headless, including neuron-app. A display-backed WSL GUI test stalled, so live Linux GUI behavior is not verified by this run.
• .\validate.ps1 -Mode lint -Locked passed. The existing rustfmt advisory remains as documented.
• Macro skill validator, release workflow YAML parse, and 59 local documentation links passed.
• No real device or live GUI interaction was exercised for this PR.

Before this can merge

• I have read and accept the Woflo Labs Contributor Agreement 1.0 for this contribution, and I have authority to submit it.