deno lint no-import-prefix conflicts with swamp's required npm:/jsr: inline specifiers

Description

Swamp extension models require npm: and jsr: inline import specifiers (e.g., import { z } from "npm:zod@4") because there is no deno.json or import map managed by swamp. However, Deno's built-in linter flags every one of these with the no-import-prefix rule:

error[no-import-prefix]: Inline 'npm:', 'jsr:' or 'https:' dependency not allowed

This forces every extension model file and test file to include a // deno-lint-ignore no-import-prefix suppress comment on each inline import.

Steps to Reproduce

1. Create a swamp extension model with import { z } from "npm:zod@4";
2. Run deno lint extensions/models/
3. Observe no-import-prefix error on every inline specifier

Expected Behavior

Swamp should either:

• Generate/manage a deno.json with an import map so bare specifiers work, OR
• Document the // deno-lint-ignore no-import-prefix workaround as expected, OR
• Provide a lint config that suppresses this rule for extension model directories

Environment

• swamp version: 20260318.021802.0-sha.3848499d
• Deno version: 2.2.8
• OS: macOS Darwin 25.3.0

Related

• #617 — lockfile strategy for extension model npm deps (same root cause: no deno.json managed by swamp)

Summary

The fix would involve swamp managing a deno.json (or deno.jsonc) in the extensions directory that maps bare specifiers to their npm:/jsr: equivalents. This would resolve both the lint warnings and the lockfile gap from #617 in one change. Affected component: extension model scaffolding and the swamp extension CLI commands.