Fix all npm audit vulnerabilities by upgrading dependencies

[lyonsil]

@typescript-eslint/* ^6 → ^8

• Fixes minimatch ReDoS vulnerabilities

copy-webpack-plugin ^12 → ^14

• Fixes serialize-javascript RCE vulnerability

eslint-config-erb removed

• Source of the peer dep conflicts; replaced by direct configs

eslint-config-airbnb-base removed

• Redundant — eslint-config-airbnb already depends on it

eslint-config-airbnb added

• Previously pulled in by erb

eslint-config-prettier added

• Previously pulled in by erb

eslint-plugin-prettier added

• Previously pulled in by erb

@stylistic/eslint-plugin-ts ^2.13.0 added

• Provides lines-between-class-members rule with exceptAfterOverload support, which was removed from @typescript-eslint v8

ESLint behavioral parity:

• eslint-config-airbnb-typescript was never active — erb installed it but never extended it. No rules are lost.
• All 4 rules erb explicitly set are preserved (3 default to off anyway; no-param-reassign explicitly added).
• lines-between-class-members now uses @stylistic/ts/lines-between-class-members to preserve the original exceptAfterOverload: true option.

tsconfig.lint.json change: allowJs: true only affects the lint-specific tsconfig (not builds), and is the official replacement for the removed createDefaultProgram.

Note: The @typescript-eslint v6 → v8 upgrade may cause some rules to flag new issues in downstream repos due to bug fixes and stricter detection in v8. This is inherent to the major version upgrade required by the security fixes.

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This change is 

[Copilot]

Pull request overview

Updates lint/build toolchain dependencies and ESLint/TypeScript lint configuration to address npm audit security findings (notably minimatch ReDoS and serialize-javascript RCE) while preserving prior lint behavior where possible.

Changes:

• Upgrades key devDependencies (notably @typescript-eslint/* to v8 and copy-webpack-plugin to v14) and bumps Volta Node version.
• Replaces eslint-config-erb/eslint-config-airbnb-base with explicit airbnb + prettier + plugin-based configs and adds @stylistic/eslint-plugin-ts for rule parity.
• Updates tsconfig.lint.json to enable allowJs for lint-only type-aware parsing.

Reviewed changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated no comments.

File	Description
tsconfig.lint.json	Enables allowJs in the lint-specific TS config to support type-aware linting without createDefaultProgram.
package.json	Upgrades/adjusts linting and build dependencies to remediate audit vulnerabilities and resolve peer conflicts.
.eslintrc.cjs	Reworks ESLint config to explicitly extend Airbnb/Prettier/plugin presets and swaps lines-between-class-members to @stylistic/ts rule.

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[tjcouch-sil]

Very nice! Same things apply here as in the other PR.

@tjcouch-sil reviewed 6 files and all commit messages, and made 1 comment.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on irahopkinson).