Data Streams: remove verifier fee from samples and warn in schema

[dev-dist]

This pull request updates the Data Streams sample contracts to remove legacy fee handling logic and interfaces, reflecting the switch to subscription-based billing. The main changes are the removal of all FeeManager-related code, documentation updates to clarify that LINK approvals and fee quoting are no longer required, and simplification of the report verification process.

Fee handling removal and simplification:

• All imports, interface definitions, and code related to FeeManager, RewardManager, and LINK/ERC20 approvals have been removed from ClientReportsVerifier.sol, StreamsUpkeep.sol, and StreamsUpkeepRegistrar.sol. [1] [2] [3] [4] [5]
• The report verification process now directly calls VerifierProxy.verify() or verifyBulk() with empty bytes for the parameter payload, as subscription billing does not require fee metadata or approvals. [1] [2] [3]

Documentation and comments:

• All comments and docstrings have been updated to clarify that Data Streams uses subscription-based billing, and that no LINK tokens or fee approvals are required for verification calls. [1] [2] [3] [4] [5] [6]
• Field comments for nativeFee and linkFee in report structs have been updated to indicate these are legacy fields and not used for subscription billing. [1] [2] [3] [4]

Interface and code cleanup:

• The custom IFeeManager interface and related methods have been removed from all sample contracts. [1] [2] [3]
• Unused state variables related to fee management (e.g., FEE_ADDRESS) have been deleted. [1] [2]

These changes make the sample contracts easier to understand and use, aligning them with the current Data Streams billing model.

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Project	Deployment	Actions	Updated (UTC)
documentation	Ready	Preview	Jul 23, 2026 10:05pm

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