refactor(aria): share the none role definition with presentation

[chutchins25]

Models presentation as a synonym of none and removes the hardcoded ['none', 'presentation'] membership checks, per @WilcoFiers on #4656.

Stacked PR — targets chut/4656-role-image-synonym (#4656), which introduced the synonym mechanism this builds on. GitHub will auto-retarget to develop once #4656 merges.

What & why

Uses the synonym mechanism from #4656:

• presentation role gets synonym: 'none', so getExplicitRole/getRole resolve it to the canonical none.
• The implicit presentation role (empty-alt <img>) is also normalized to none at the data level (implicit-html-roles.js), so getRole never returns 'presentation' from either the explicit or implicit path.

With role resolution always yielding none, the scattered ['none', 'presentation'].includes(role) checks that read from getRole/getExplicitRole collapse to a single role === 'none' — 18 sites simplified.

Intentionally left with both terms

• fallbackrole-evaluate.js — reads raw role attribute tokens (tokenList), so it needs the literal presentation and none tokens.
• presentation-role-conflict.json (CSS selector) and html-elms.js allowedRoles arrays — raw/selector paths.
• lookup-table.js evaluateRoleForElement — has no call sites, so its input couldn't be verified as normalized.

Behavior note

getRole/getExplicitRole now return 'none' where they previously could return 'presentation' (they're synonyms — none is the canonical term). End-to-end rule results are unchanged (all integration + virtual-rule suites pass without expectation changes); only internal commons role-resolution output and the corresponding unit-test expectations changed.

Tests

• implicit-role, get-role (13 inheritance cases), presentational-role, aria-allowed-role — result expectations updated presentation→none.
• Full commons / checks / integration / virtual-rule suites green; no generated-file drift.

Closes #5249

[straker]

Per discussion in #5248 (review), the only thing this pr should do is extract the role defintion in aria-roles for none into it's own object and spread it to the none and presentation roles so they remain linked.

[Copilot]

Pull request overview

Refactors the ARIA standards role definitions to centralize the shared spec for the none and presentation roles, aiming to keep the two role entries consistent as the codebase moves toward treating them equivalently.

Changes:

• Introduces a shared noneRole object for common role metadata.
• Replaces duplicated inline definitions for none and presentation with spreads of noneRole.

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