Clarify that coding-agents-prompting-flow.md is a Rosetta KB path, no…

[YevheniiaLementova]

Summary

• Added a note to the "Prompt Changes" section in CONTRIBUTING.md and docs/web/docs/contributing.md clarifying that instructions/r2/grid/workflows/coding-agents-prompting-flow.md is a Rosetta knowledge base path served via Rosetta MCP, not a file in this repository
• Updated example labels to make it explicit that all examples require Rosetta MCP to resolve the grid scope from the knowledge base

[github-actions]

Rosetta Triage Review

Summary: This PR adds a clarifying note to the "Prompt Changes" section of CONTRIBUTING.md (and its docs/web mirror) explaining that instructions/r2/grid/workflows/coding-agents-prompting-flow.md is a Rosetta knowledge base path served via Rosetta MCP — not a file in this repository — and updates the examples header to reflect that all listed examples require Rosetta MCP to resolve the grid scope.

Findings:

• Change is documentation-only (+7/-3 lines across 2 files); no code, no tests affected
• Both files (CONTRIBUTING.md and docs/web/docs/contributing.md) are updated consistently — no drift between the two
• Clarification accurately describes the enterprise grid scope as an MCP-served extension not present in the OSS repo tree
• Example 3 renamed from "Using Rosetta MCP" to "Explicit KB acquisition (alternative syntax)" — more precise and self-explanatory
• PR body clearly explains the motivation (contributor confusion about file location)

Suggestions:

• No issues found; the change is accurate, focused, and well-described

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