Add go-aip guidelines for resource-oriented gRPC APIs

[gonzaloserrano]

Add comprehensive reference document covering Google AIP standards
with einride/aip-go: resource names, standard methods, pagination,
filtering, ordering, field masks, and field behavior annotations.

https://claude.ai/code/session_01KUbKvTowcMQbj7Wn3oWr7B

[cubic-dev-ai]

3 issues found across 4 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="skills/gopilot/reference/go-aip.md">

<violation number="1" location="skills/gopilot/reference/go-aip.md:229">
P1: `filtering.ProtoDeclarations` does not appear to exist in the einride/aip-go library. The filtering package provides `filtering.NewDeclarations(...)` with explicit `DeclareIdent` calls to define the schema. Consider removing this section or replacing with the documented approach.</violation>

<violation number="2" location="skills/gopilot/reference/go-aip.md:259">
P1: `field.Path` is a `string`, not `[]string`, so `strings.Join(field.Path, ".")` won't compile. According to the [einride/aip-go ordering docs](https://pkg.go.dev/go.einride.tech/aip/ordering), `Field.Path` is already a dot-separated string. Use `field.Path` directly.</violation>
</file>

<file name="skills/gopilot/SKILL.md">

<violation number="1" location="skills/gopilot/SKILL.md:351">
P2: Field masks AIP number is incomplete — should reference AIP-161 (the canonical field mask AIP), not just AIP-134 (which is the Update method). The project's own `reference/go-aip.md` correctly cites both: `(AIP-134, AIP-161)`.</violation>
</file>

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