Agent Skills: lisa-linear-access

Vendor-neutral access layer for Linear. Linear skills MUST delegate through this skill rather than calling Linear MCP tools or Linear GraphQL directly. Per the credential-substrate-precedence contract, resolves LINEAR_API_KEY + Linear GraphQL first — ahead of the Linear MCP — whenever the key is present and identity-matches the configured workspace/team, and falls back to the Linear MCP when the token path is unavailable. Identity-match is mandatory on both substrates.