add 2.0 integration guide

[tt-cll]

No description provided.

[github-actions]

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[Copilot]

Pull request overview

Adds a dedicated CCIP 2.0 integration guide to the deployment tooling documentation, and links it from the main docs index and the existing “Implementing Adapters” guide so integrators can follow a 2.0-specific path.

Changes:

• Add new CCIP 2.0 Integration Guide doc covering 2.0-specific interfaces, registries/dispatch flow, and an integration checklist.
• Link the new guide from deployment/docs/index.md.
• Add an upfront callout in implementing-adapters.md redirecting 2.0 integrators to the new guide.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
deployment/docs/index.md	Adds the new 2.0 guide to the documentation index table.
deployment/docs/implementing-adapters.md	Adds a prominent note directing CCIP 2.0 integrators to the new guide.
deployment/docs/ccip-2.0-integration-guide.md	New end-to-end CCIP 2.0 integration documentation (interfaces, flow, registration, checklist).

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[Copilot]

These registration snippets use chainsel.FamilyMyChain, but most other docs in deployment/docs/ use the chain_selectors import name (e.g. implementing-adapters.md). For consistency and to reduce copy/paste friction, consider using chain_selectors.FamilyMyChain (or explicitly show the import/alias you expect readers to use).

Suggested change

	adapters.GetDeployChainContractsRegistry().Register(chainsel.FamilyMyChain, &MyDeployAdapter{})
	adapters.GetDeployChainContractsRegistry().Register(chain_selectors.FamilyMyChain, &MyDeployAdapter{})

[Copilot]

In the sequence diagram, TokenAdapterRegistry.GetTokenAdapter() is shown without parameters. In code the lookup requires (chainFamily, version), so it may be clearer to annotate that here (or rename the callout to something like "Resolve token adapter by (family, poolVersion)"), to prevent readers from looking for a no-arg method.

Suggested change

	CS->>Reg: TokenAdapterRegistry.GetTokenAdapter()
	CS->>Reg: TokenAdapterRegistry.GetTokenAdapter(chainFamily, version)

[Copilot]

The comparison table says "No OCR" for 2.0, but the codebase still relies on OCR key bundles (OCR2) for node chain config/signing keys in the 2.0 offchain flow. Consider changing this cell to something more precise like "No OCR3 (OffRamp OCR3 config not used in 2.0)" to avoid implying that OCR-related configuration disappears entirely.

Suggested change

	| **OCR** | OCR3 configured on OffRamp | No OCR -- off-chain consensus handled differently |
	| **OCR** | OCR3 configured on OffRamp | No OCR3 on OffRamp -- OCR key bundles still used elsewhere in 2.0 offchain flow |

[makramkd]

nit: this all renders on the same line, bulleting them may look cleaner:

Suggested change

	**Source:** [v2_0_0/adapters/deploy_chain_contracts.go](../v2_0_0/adapters/deploy_chain_contracts.go)
	**Registry:** `DeployChainContractsRegistry` via `adapters.GetDeployChainContractsRegistry()`
	**Key:** `chainFamily` (version-agnostic within 2.0)
	* **Source:** [v2_0_0/adapters/deploy_chain_contracts.go](../v2_0_0/adapters/deploy_chain_contracts.go)
	* **Registry:** `DeployChainContractsRegistry` via `adapters.GetDeployChainContractsRegistry()`
	* **Key:** `chainFamily` (version-agnostic within 2.0)

[makramkd]

Suggested change

	**Source:** [v2_0_0/adapters/chain_family.go](../v2_0_0/adapters/chain_family.go)
	**Registry:** `ChainFamilyRegistry` via `adapters.GetChainFamilyRegistry()`
	**Key:** `chainFamily` (version-agnostic within 2.0)
	* **Source:** [v2_0_0/adapters/chain_family.go](../v2_0_0/adapters/chain_family.go)
	* **Registry:** `ChainFamilyRegistry` via `adapters.GetChainFamilyRegistry()`
	* **Key:** `chainFamily` (version-agnostic within 2.0)

[makramkd]

This is good documentation - though I wonder if we should have it in the devenv package as well (or instead?).

[tt-cll]

yeah maybe this section can be sparser on devenv. I wanted to have something explaining how the tooling API is called for someone performing an integration, but maybe that detail should be in a different doc

[github-actions]

Metric	tt/guide	main
Coverage	70.1%	69.8%