chore(claude): encode model-naming convention + AsSpan-on-hot-paths rule

[emeraldleaf]

Summary

Encodes two rules (requested), both framed to fit NextAurora's actual context rather than as blanket assertions that would contradict existing rules.

1. Model naming (intent-based, by role)

Source tip: "prefer Request/Response over Dto." Encoded as the convention NextAurora already follows — which is more intent-based than the suggestion:

• CQRS messages: *Command (writes) / *Query (reads) — more specific than a generic *Request (says write-vs-read + flows the Wolverine pipeline)
• gRPC contracts: *Request / *Response pairs (gRPC idiom, already used in CatalogService)
• Read projections: *Dto — acceptable only here (query-result shape, not HTTP-coupled, so not renamed to *Response)

Rule in one line: generic *Dto on a request model hides intent — name it by what it does; reserve *Dto for read projections. Deliberately does not mandate "Request/Response everywhere" — that would downgrade the write side from the more-specific Command/Query.

Encoded in CLAUDE.md "Coding Standards" + a .coderabbit.yaml **/*.cs naming line (flag a generic *Dto on a new command/query; don't recommend renaming existing read-projection DTOs).

2. AsSpan over Substring (profiled hot paths only)

Zero-allocation slicing — real win in synchronous, hot, string-heavy loops. Encoded with two guardrails so it's a narrow tool, not a default:

• Governed by "Measure before optimizing" — apply where profiling shows allocation pressure, not reflexively.
• Span<T> is a ref struct — can't cross an await boundary, so it's rarely usable in NextAurora's async-everywhere handlers (the compiler stops you).

No such hot path exists today (string work is incidental; the bottleneck is always I/O), so the rule is explicitly preventative. CLAUDE.md "Performance Rules" only — no .coderabbit.yaml/reviewer surface (it's a judgment-on-profiling call, not a code-shape check), same scoping as the streams rule.

Paraphrase-drift audit (per CLAUDE.md change)

Run /check-rules locally to audit paraphrases against this diff. Done — both rules are net-new; no existing See CLAUDE.md marker covers model-naming or AsSpan, so nothing to realign. The naming rule codifies the de-facto convention already visible in the type names; AsSpan has no existing usage to conflict with. No drift.

Note on the framing

I'd originally recommended against encoding both (the AsSpan tip is a micro-opt that doesn't fit an I/O-bound async app; the naming tip is superseded by NextAurora's CQRS naming). Per direction to add them, they're encoded as the NextAurora-accurate versions — capturing the real nuance (when AsSpan actually applies; why Command/Query beats generic Request) rather than blanket assertions that would conflict with "Measure before optimizing" and the CQRS naming already in use.

Test plan

• Paraphrase-drift audit run — no drift
• Both rules consistent with existing CLAUDE.md ("Measure before optimizing", CQRS conventions)
• CodeRabbit applies the new MODEL NAMING line on next PR touching **/*.cs

🤖 Generated with Claude Code

Summary by CodeRabbit

• Documentation

  • Added intent-based model naming guidance distinguishing command/query, gRPC request/response, and read-projection roles; cautions against using generic DTO names for requests.
  • Added performance guidance recommending measured use of zero-allocation string slicing (AsSpan vs Substring) with async/escaping guardrails.

• Chores

  • Updated review/configuration guidance to enforce the new naming conventions.

[coderabbitai]

Caution

Review failed

Pull request was closed or merged during review

Walkthrough

Adds intent-based model naming guidance (CQRS, gRPC, read projections) to reviewer config and docs, and a performance guideline advising AsSpan over Substring for profiled synchronous hot paths.

Changes

Coding Standards and Performance Guidelines

Layer / File(s)	Summary
Intent-based Model Naming Conventions .coderabbit.yaml, CLAUDE.md	Defines intent-based naming patterns: *Command/*Query for CQRS, *Request/*Response for gRPC, and reserves *Dto for read-side projections; warns against generic *Dto on request models.
Performance Guidelines for String Slicing CLAUDE.md	Recommends AsSpan over Substring for zero-allocation slicing on profiled synchronous hot paths and documents Span<T>/ReadOnlySpan<T> ref struct async/escape constraints.

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🎯 2 (Simple) | ⏱️ ~10 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely summarizes the two main changes: encoding model-naming convention and adding the AsSpan-on-hot-paths rule into documentation and tooling.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch chore/encode-asspan-and-model-naming

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Codecov Report

✅ All modified and coverable lines are covered by tests.

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[coderabbitai]

Actionable comments posted: 0