chore: update nv27 codename

[rjan90]

Proposed Changes

Updates the nv27 codename to Goldenweek, to be in line with filecoin-project/community#74 (comment)

Additional Info

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[Copilot]

Pull Request Overview

Updates the Filecoin network version 27 (nv27) codename from "Xx" to "Goldenweek" to align with community discussions and official naming conventions.

• Renames all references to UpgradeXxHeight to UpgradeGoldenweekHeight across configuration files
• Updates corresponding environment variable names and documentation
• Modifies API response structures to reflect the new upgrade name

Reviewed Changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
node/impl/full/state.go	Updates API response to use new upgrade field name
documentation/en/api-methods-v1-stable.md	Updates API documentation example response
documentation/en/api-methods-v0-deprecated.md	Updates deprecated API documentation example response
chain/consensus/filcns/upgrades.go	Updates upgrade configuration to reference new height constant
build/openrpc/gateway.json	Updates OpenRPC schema with new upgrade field name
build/buildconstants/params_*.go	Renames upgrade height constants and environment variables across all network configurations
api/types.go	Updates ForkUpgradeParams struct field name

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[BigLep]

Looks good. Just need to change to UpgradeGoldenWeekHeight per verbal to be consistent.